Variable Size Regions! Support for prehash RegionSizeX and large patches. (WIP)

Mostly from Ukando, tweaked a bit to be cleaner, and a little less dramatic.

decode_patch_header now takes a bool optionally, as third argument.
_PREHASH_RegionSizeX is the only used of the two _PREHASH_RegionSize*.
llsurface.cpp: Copy the connectNeighbor for variable size regions almost directly from Ukando
llsurfacepatch.cpp: Patch code from ukando and voodoo.
Changed hardcoded 256 constants and such to width functions in: llglsandbox.cpp, llsurface.cpp, llviewerregion.cpp, llviewerparcelmanager, llviewerparcelmgr.cpp, llvowater.cpp, llworld.cpp
Use region specific width in: llagent.cpp, llglsandbox.cpp, llmanip.cpp, llmanipscale.cpp, llpanelobject.cpp, llviewerbject.cpp, llwind.cpp
Use 256 in llnetmap.cpp in places...
llfloaterregioninfo.cpp: Aurora grid has wacky textures.
Add LLViewerParcelMgr::widthUpdate() for updating mParcelsPerEdge given a region's width. Used in llstartup now.
Add LLWorld::setWidth() for getting a region's size from LLMessageSystem pointers and setting mWidth and mWidthInMeters, accordingly. Called in llviewermessage.cpp as well.
Merge branch 'master' into VarRegion
AuroraSim: non-power-of-two support.
AuroraSim: More tiny bits to help life be normal on the grid.
Harden agains network packet overruns

Patch by NickyD from Firestorm
Aurora var region support
Firestorm patch by Cinders
Adopted from Angstrom viewer with assistance of nhede Core
and Revolution Smythe.
Merge branch 'master' of git://github.com/Lirusaito/SingularityViewer
Merge branch 'VarRegion' of https://github.com/Lirusaito/SingularityViewer into aurora-sim

Merged cleanly:
	indra/llkeyframewalkmotion.cpp - 36e6946c9610d330525a2f2afd46d29bd126389a - worked around a bug in Aurora walking motion
	indra/llrender/llimagegl.cpp - fa8e1f033bde94b48156c4606db3751604e4de4f - An llerrs here becomes an llwarns, to avoid bothering the user with non power of two dimensioned images
	indra/newview/llmanip.cpp, indra/newview/llmanipscale.cpp - "Changed hardcoded 256 constants and such to width functions" - a50f0008b2afb78b4a1f63fe4defbefb49800b34
	indra/newview/llpatchvertexarray.cpp - fa8e1f033bde94b48156c4606db3751604e4de4f - Support patches of non power of two width
	indra/newview/llworldmap.h - conflict

Conflicts:
	indra/llmessage/patch_code.cpp - My version cleaned up a bit of code duplication, so this was applied, within the new tags
	indra/llmessage/patch_code.h - b_large_patch in decode_patch_header defaults to false, indra/newview/llcloud.cpp patch removed.
	indra/llmessage/patch_dct.h - false positive
	indra/newview/llagent.cpp - false positive
	indra/newview/llfloaterregioninfo.cpp - nonsl wacky textures support meets the refactor.
	indra/newview/llfloaterworldmap.cpp - false positive
	indra/newview/llglsandbox.cpp - false positive
	indra/newview/llnetmap.cpp - small changes for type consistency brought into FS' patch, nothing important; also adds change to LLNetMap:draw removing getRegionWidthInMeters to keep using the constant REGION_WIDTH
	indra/newview/llpanelobject.cpp - Get the region width of the object we're editing for maximum pasted x/y coords
	indra/newview/llstartup.cpp - [Fixes old issues] My old patch did not fully use first_sim_size_x here, this has been fixed.  The unused first_sim_size_y has been removed.
	indra/newview/llsurface.cpp - rebuildWater isn't used, removed for now.  Styling conflicts otherwise.
	indra/newview/llsurfacepatch.cpp - remove FS patch that comments out code that isn't even in the modern source; cleaned up a mess of tags with more clear explanation, perhaps it can be expanded upon though.  Some styling conflicts.
	indra/newview/llviewermessage.cpp - Fix the problem? setRegionWidth by number.
	indra/newview/llviewerobject.cpp - false positive
	indra/newview/llviewerparcelmgr.cpp - just styling conflicts
	indra/newview/llviewerparcelmgr.h - false positive
	indra/newview/llviewerparceloverlay.cpp - false positive
	indra/newview/llviewerparceloverlay.h - false positive
	indra/newview/llviewerregion.cpp - cleaned up LLViewerRegion::getCompositionXY patches, they're more in the way than they're worth; removed DispatchOpenRegionSettings capability mention for now, it's not related to variable regions.  Also remove rebuildWater, it's not used right now.
	indra/newview/llvowater.cpp - false positive
	indra/newview/llwind.cpp - remove decode_patch_header patches for false, since we have a default; otherwise false positive.
	indra/newview/llworld.*
		- [Fixes old issues] Remove setRegionWidth by LLMessageSystem as the messages used are not always the same, the by number one remains of course.
		- Retained separation of connecting neighbors through the old method when the width is 256
		- updateLimits() would never have been merged in, we have an entirely different grid manager, therefore it's removed.
		- Fix the stupidity passed on over the years wherein a static constant variable would hold the same value as the first call to setLandFarClip..
	indra/newview/llworldmap.cpp - 36e6946c9610d330525a2f2afd46d29bd126389a Aurora map workaround stuffs, parts removed; rework of LLWorldMap::simInfoFromHandle
	indra/newview/llworldmap.h - Cleaned up organization, avoid making members public, and fixed tagging
[VarRegions] Made the radar aware that region width may not be 256 always anymore
[VarRegions] Fix copy slurl on map to take the fmod of the x and y against the width of the region in question, instead of 256