Manual merge from default branch.

indra/cmake/Copy3rdPartyLibs.cmake

indra/cmake/Variables.cmake

indra/llcommon/CMakeLists.txt

indra/llcommon/imageids.cpp

indra/llcommon/imageids.h

indra/llcommon/indra_constants.cpp

indra/llcommon/indra_constants.h

indra/llcommon/linden_common.h

indra/llcommon/lldictionary.cpp

indra/llcommon/lldictionary.h

indra/llcommon/llpreprocessor.h

indra/llcommon/llsd.cpp

indra/llcommon/llsd.h

indra/llcommon/llsingleton.h

indra/llcommon/llsys.cpp

indra/llmath/CMakeLists.txt

indra/llmessage/CMakeLists.txt

indra/llmessage/llareslistener.cpp

indra/llmessage/lldatapacker.cpp

indra/llmessage/lldatapacker.h