Superficial header file fixes.

EXT-7888 FIXED Opening a gesture from an in-world object shows gesture floater with blank information
EXT-7909 FIXED Cleanup llpreviewgesture #include files

Fixed an issue that was causing gesture asset loading to fail.
Also did header file cleanup.

--HG--
branch : product-engine

and reduce unnecessary dependencies and incredibuild wedging.  Hopefully in
the long run this will reduce build time.  Also cleaned up a lot of header
file usage to conform better to the coding standard.

reviewed by james and steve.

EXT-1339 Create onClose method in LLFloater, and remove most bindings to mCloseSignal.  In the vast majority of cases, mCloseSignal is being bound to an onClose function.  Just make it virtual and be done with it.  Renamed a couple of LLPanel close methods to onClosePanel() to distinguish them.  Reviewed with Richard.

svn merge -r 128442:129343 svn+ssh://svn.lindenlab.com/svn/linden/branches/skinning/skinning-18 into svn+ssh://svn.lindenlab.com/svn/linden/branches/viewer/viewer-2.0.0-3

ignore-dead-branch

svn merge -r108355:109316
svn+ssh://svn.lindenlab.com/svn/linden/branches/moss/maint-viewer-12-uploadfees-qa108314

Whew.

Result of svn merge -r107256:107258 svn+ssh://svn/svn/user/phoenix/license_2009_merge into trunk. QAR-1165

svn merge -r106715:HEAD svn+ssh://svn.lindenlab.com/svn/linden/branches/q/notifications-merge-r106715 .  QAR-1149 -- Final merge of notifications to trunk.

dataserver-is-deprecated

QAR-424

EFFECTIVE MERGE: svn merge -r 71520:73420  svn+ssh://svn/svn/linden/branches/maintenance-3 into release
ACTUAL MERGE: svn merge -r 75074:75114 svn+ssh://svn/svn/linden/qa/maintenance-3-merge-75067 into release

Result of svn merge -r71162:71205 svn+ssh://svn/svn/linden/branches/new-license into release. only changes files which are not deployed or the comments section of code.

ACTUAL MERGE: svn merge -r 69685:69687 svn+ssh://svn/svn/linden/branches/release-r69649-maintenance-sync
EQUIVALENT TO: svn merge -r 68118:69663 svn+ssh://svn/svn/linden/branches/maintenance-r68999

EFFECTIVE MERGE: svn merge -r 66133:68118 svn+ssh://svn/svn/linden/branches/maintenance into release

Actual action: branched maintenance-r68118, merged in release, then copied result into release