merge changes to improve build times

autobuild.xml

build.sh

indra/CMakeLists.txt

indra/cmake/00-Common.cmake

indra/cmake/LLAddBuildTest.cmake

indra/cmake/Prebuilt.cmake

indra/cmake/Variables.cmake

indra/llcommon/llapp.cpp

indra/llui/llbutton.h

indra/llui/llfloaterreg.h

indra/llui/llfocusmgr.cpp

indra/llui/llfocusmgr.h

indra/llui/lliconctrl.h

indra/llui/lllineeditor.h

indra/llui/llloadingindicator.h

indra/llui/llmultislider.cpp

indra/llui/llpanel.h

indra/llui/llprogressbar.cpp

indra/llui/llprogressbar.h

indra/llui/llslider.h