EXT-7485 FIXED Provided update of 'save as' button status and save outfit panel status.

1 published LLCOFObserver as LLOutfitObserver(moved from llpaneloutfitedit.cpp to lloutfitobserver.h)
2 decoupled outfit edit panel and observer by replacing pointer to panel with signals and made observer as singleton
3 moved call of LLAppearanceMgr::getInstance()->updateIsDirty() from outfit edit panel to observer(discussed with IB)
4 modified updating of combo button state on outfit panel using LLOutfitObserver
5 modified refresh of outfit name and status on outfit change event using LLOutfitObserver
6 removed unnecessary LLWatchForOutfitRenameObserver that caused excessive updates of outfit panel status name

--HG--
branch : product-engine