In some places we want to log the same information but with different severity
depending on specifics. In other cases we need to test the availability of the
logging subsystem before engaging it. LL_VLOGS() accepts an LLError::ELevel
argument that can differ with each call, while retaining the desirable feature
of deciding only once for each level.

We've had this functionality buried in llerror.cpp for years. Make it
available for callers outside llerror.cpp too.

If the coro is given something other than a map from the http then move the return into a body section.
Changed windlight to use a coroutine and the new LLCore::Http libarary.
Extra comments into Event Polling.

SH-4577 WIP Interesting: viewer crashed when clicking a offline Conversation containing a shared object
potential fix by making instance tracker allow key collisions for LLToastNotifyPanel
changed assertion macro to use original unpreprocessed source code
renamed instance tracker behavior macros to use LL prefix
added RestoreCameraPosOnLogin setting to optionally restore old camera positioning behavior

changed unit declarations macros to make a lot more sense

made getPrimaryAccumulator return a reference since it was an
always non-null pointer
changed unit conversion to perform lazy division in order to avoid truncation
of timer values

fixed bad search and replace

added convenience types for units F32Seconds, etc.

SH-4346 FIX: Interesting: some integer Statistics are displayed as floating point after crossing region boundary
made llerrs/infos/etc properly variadic wrt tags
LL_INFOS("A", "B", "C") works, for example
fixed unit tests
remove llsimplestat

replace llinfos, lldebugs, etc with new LL_INFOS(), LL_DEBUGS(), etc.

consolidated most indra-specific constants in llcommon under indra_constants.h
fixed issues with operations on mixed unit types (implicit and explicit)
made LL_INFOS() style macros variadic in order to subsume other logging methods
such as ll_infos
added optional tag output to error recorders

there are no samples during the time period.
added hasValue to SampleAccumulator so we don't print a value when we don't have
a single sample yet
added some disabled log output for scene load timing

BUG-2707 fix comment typos, remove unnecessary winmm_shim changes, and revert 2672 fix included only for local integ test

MAINT-2740 convert to std::string based API for OutputDebug wrapper cleanliness after sage counsel (slight refrain)

MAINT-2740 and MAINT-2672 rework after code review for 2740 fix and include 2672 fix needed for doing local integ tests

MAINT-2740 make use of OsOutputDebugString _DEBUG only to avoid interactions between Win 32-bit SEH and boost coroutine fiber stack handling

BUG-2707 make use of OsOutputDebugString _DEBUG only on Windows to avoid throwing unhandlable exceptions in coroutines in RelWithDebInfo builds

accessed through the static LLThread::tldata().
Currently this object contains two (public) thread-local
objects: a LLAPRRootPool and a LLVolatileAPRPool.

The first is the general memory pool used by this thread
(and this thread alone), while the second is intended
for short lived memory allocations (needed for APR).
The advantages of not mixing those two is that the latter
is used most frequently, and as a result of it's nature
can be destroyed and reconstructed on a "regular" basis.

This patch adds LLAPRPool (completely replacing the old one),
which is a wrapper around apr_pool_t* and has complete
thread-safity checking.

Whenever an apr call requires memory for some resource,
a memory pool in the form of an LLAPRPool object can
be created with the same life-time as this resource;
assuring clean up of the memory no sooner, but also
not much later than the life-time of the resource
that needs the memory.

Many, many function calls and constructors had the
pool parameter simply removed (it is no longer the
concern of the developer, if you don't write code
that actually does an libapr call then you are no
longer bothered with memory pools at all).

However, I kept the notion of short-lived and
long-lived allocations alive (see my remark in
the jira here: https://jira.secondlife.com/browse/STORM-864?focusedCommentId=235356&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-235356
which requires that the LLAPRFile API needs
to allow the user to specify how long they
think a file will stay open. By choosing
'short_lived' as default for the constructor
that immediately opens a file, the number of
instances where this needs to be specified is
drastically reduced however (obviously, any
automatic LLAPRFile is short lived).

***

Addressed Boroondas remarks in https://codereview.secondlife.com/r/99/
regarding (doxygen) comments. This patch effectively only changes comments.

Includes some 'merge' stuff that ended up in llvocache.cpp
(while starting as a bug fix, now only resulting in a cleanup).

***

Added comment 'The use of apr_pool_t is OK here'.

Added this comment on every line where apr_pool_t
is correctly being used.

This should make it easier to spot (future) errors
where someone started to use apr_pool_t; you can
just grep all sources for 'apr_pool_t' and immediately
see where it's being used while LLAPRPool should
have been used.

Note that merging this patch is very easy:
If there are no other uses of apr_pool_t in the code
(one grep) and it compiles, then it will work.

***

Second Merge (needed to remove 'delete mCreationMutex'
from LLImageDecodeThread::~LLImageDecodeThread).

***

Added back #include <apr_pools.h>.

Apparently that is needed on libapr version 1.2.8.,
the version used by Linden Lab, for calls to
apr_queue_*. This is a bug in libapr (we also
include <apr_queue.h>, that is fixed in (at least) 1.3.7.

Note that 1.2.8 is VERY old. Even 1.3.x is old.

***

License fixes (GPL -> LGPL). And typo in comments.
Addresses merov's comments on the review board.

***

Added Merov's compile fixes for windows.

This makes logs look less scary on Linux, in-line with other platforms.