Issue 1151: Add share to LLAvatarActions

Syncs LLGiveInventory and LLFloaterAvatarPicker with upstream.
Syncsyncsync~

Translators:
menu_inventory.xml menu_radar.xml and menu_avs_list.xml: Share
notifications.xml: ShareNotification, ShareItemsConfirmation, ShareFolderConfirmation, ItemsShared
strings.xml: share_alert
Only disable friend items that have rights changed (scope reduction surgery)

Thanks to Deltek for finding this one!