Cache some hot path settings

indra/newview/lldrawpoolalpha.cpp

indra/newview/lldrawpoolterrain.cpp

indra/newview/lldrawpoolwater.cpp

indra/newview/llsettingsvo.cpp

indra/newview/lltoolpie.cpp

indra/newview/lltracker.cpp

indra/newview/llviewerdisplay.cpp

indra/newview/llviewermedia.cpp

indra/newview/llviewerobjectlist.cpp

indra/newview/llviewerparceloverlay.cpp

indra/newview/llviewertexlayer.cpp

indra/newview/llviewertexture.cpp

indra/newview/llviewerwindow.cpp

indra/newview/llvoavatar.cpp

indra/newview/llvoavatarself.cpp