Respect always rez under owned land group setting for objects
duplicated by shift-dragging or duplicating.

Based on Phoenix changeset 5b50018c63d4 by Kadah
Reworked name loading for vivox speaker list. LLSpeaker now boost::signals2::trackable to avoid accessing after destruction. Opening new sessions via doubleclick on list(sessions managed by legacyname) or using the mute button(legacyname needed to exclude lindens) are both disabled until namecache lookup complete.
Merge remote-tracking branch 'shyotl/sunshine'