Port Catznip's snooze group feature

indra/llui/llaccordionctrl.cpp

indra/llui/llaccordionctrl.h

indra/newview/llfloaterimnearbychat.cpp

indra/newview/llfloaterimsession.cpp

indra/newview/llfloaterimsession.h

indra/newview/llfloaterimsessiontab.cpp

indra/newview/llfloaterimsessiontab.h

indra/newview/llgroupactions.cpp

indra/newview/llgroupactions.h

indra/newview/llpanelgroup.cpp

...newview/skins/default/textures/icons/Conv_toolbar_pay.png

...view/skins/default/textures/icons/Conv_toolbar_snooze.png

...ew/skins/default/textures/icons/Conv_toolbar_teleport.png

indra/newview/skins/default/textures/textures.xml

...wview/skins/default/textures/widgets/Arrow_Small_Down.png

indra/newview/skins/default/xui/en/floater_im_container.xml

indra/newview/skins/default/xui/en/floater_im_session.xml