Update/Modernize LLAvatarName and LLAvatarNameCache and _EVERYTHING_ they touch

Fairly certain this adds the feature in which the user may click the online notification to open a chat with the user coming online.

Translators may want to look at the xml changes of this change to see what to update

Removes old LegacyMultiAttachmentSupport patch
Moves LLAvatarName-centric functions into LLAvatarName from elsewhere.
Adds boost::signals2::connections to name polling places.
Removes more old icky static callbacks
Merge from Alchemy, credit where due~
Update notifications.xml to have a bunch of the tags from upstream to ease diffing

indra/newview/skins/default/xui/en-us/panel_group_bulk_ban.xml

@@ -17,17 +17,43 @@
     Group bans not sent: too many Residents selected. Group bans are limited to 100 per request.
   </panel.string>
   <panel.string
-     name="already_banned">
-    Group Invitations not sent: resident '[RESIDENT]' already banned.
+     name="ban_not_permitted">
+    Group ban not sent: you do not have 'Manage ban list' ability.
+  </panel.string>
+  <panel.string
+     name="ban_limit_fail">
+    Group ban not sent: your group have reached limit of allowed ban records.
+  </panel.string>
+  <panel.string
+     name="partial_ban">
+    Some group bans were not sent:
+[REASONS]
+  </panel.string>
+  <panel.string
+     name="ban_failed">
+    Group bans were not sent:
+[REASONS]
+  </panel.string>
+  <panel.string
+     name="residents_already_banned">
+    - The following resident(s) are already banned: [RESIDENTS].
+  </panel.string>
+  <panel.string
+     name="ban_limit_reached">
+    - Ban limit reached, following agents not banned: [RESIDENTS].
+  </panel.string>
+  <panel.string
+     name="cant_ban_yourself">
+    - You cannot ban yourself from a group.
   </panel.string>
   <text
    type="string"
    length="1"
    height="54"
-   bottom="-28"
    layout="topleft"
    left="7"
    name="help_text"
+   bottom="-28"
    word_wrap="true"
    width="200">
     You can select multiple Residents to
@@ -51,7 +77,7 @@ Resident Chooser&apos; to start.
    multi_select="true"
    name="banned_agent_list"
    tool_tip="Hold the Ctrl key and click Resident names to multi-select"
-   menu_num="0" 
+   menu_num="0"
    bottom_delta="-178"
    width="200" />
   <button

indra/newview/skins/default/xui/en-us/strings.xml

@@ -3411,6 +3411,13 @@ The
 	<!-- panel contents -->
 	<string name="PanelContentsNewScript">New Script</string>
 
+	<!-- Mute -->
+	<string name="MuteByName">(By name)</string>
+	<string name="MuteAgent">(Resident)</string>
+	<string name="MuteObject">(Object)</string>
+	<string name="MuteGroup">(Group)</string>
+	<string name="MuteExternal">(External)</string>
+
 	<!-- Region/Estate Covenant -->
 	<string name="RegionNoCovenant">There is no Covenant provided for this Estate.</string>
 	<string name="RegionNoCovenantOtherOwner">There is no Covenant provided for this Estate. The land on this estate is being sold by the Estate owner, not Linden Lab.  Please contact the Estate Owner for sales details.</string>
@@ -4161,6 +4168,8 @@ If you continue to receive this message, contact the [SUPPORT_SITE].
 	<string name="RightClick">Right click</string>
 	<string name="PowerUser4">Destroy objects - Permanently deletes an object immediately, when you don't feel like waiting for the server to respond.</string>
 	<string name="PowerUser5">Explode objects - Turns an object physical, temporary, and delinks it.</string>
+  <string name="OnlineStatus">Online</string>
+  <string name="OfflineStatus">Offline</string>
 
 	<!-- voice calls -->