[OpenSim] Grid manager

indra/newview/llfloaterpreference.cpp

indra/newview/llfloaterpreference.h

indra/newview/llpanellogin.cpp

indra/newview/llpanellogin.h

indra/newview/llviewernetwork.cpp

indra/newview/llviewernetwork.h

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

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

.../newview/skins/default/xui/en/panel_preferences_grids.xml

indra/newview/tests/lllogininstance_test.cpp

indra/newview/tests/llslurl_test.cpp

indra/newview/tests/llviewernetwork_test.cpp