SL-10293 Firestorm PR: preferences and menu search

doc/contributions.txt

indra/llui/CMakeLists.txt

indra/llui/llbutton.cpp

indra/llui/llbutton.h

indra/llui/llcheckboxctrl.h

indra/llui/llmenugl.cpp

indra/llui/llmenugl.h

indra/llui/llsearchablecontrol.h

indra/llui/llsliderctrl.h

indra/llui/lltabcontainer.cpp

indra/llui/lltabcontainer.h

indra/llui/lltextbase.cpp

indra/llui/lltextbase.h

indra/llui/lluictrl.h

indra/newview/CMakeLists.txt

indra/newview/llfloaterpreference.cpp

indra/newview/llfloaterpreference.h

indra/newview/llsearchableui.cpp

indra/newview/llsearchableui.h

indra/newview/llstatusbar.cpp