Add UI for the "invite"

- Add "More networks" button to the contact card networks section,
  which opens the list of invitable account types in a popup.
  (This "More networks" section reuses NetworkTitleViewEntry.)
- The list popup uses the same layout as the account selector
- Updated the account selector layout according to the rough visual
  spec.   Removed the tablet variant, as we use the same layout
  on the tablet too for now.
- Sends the invite intent when a type is selected.

Bug 5061956

Change-Id: I0a62126a0cf4ffeecc1a7263b124d00201b67e21
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 4069c49..2519f91 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -1281,6 +1281,9 @@
     <!-- Title for the list of all contact details that come from third-party sources (including a corporate directory) [CHAR LIMIT=20] -->
     <string name="network">Network</string>
 
+    <!-- Label of the button to open the "more networks" popup where the user can invite a contact to other social networks or services [CHAR LIMIT=32] -->
+    <string name="more_networks_button">More networks</string>
+
     <!-- Section title for the page containing the contact's social updates on the contact card [CHAR LIMIT=20]-->
     <string name="recent_updates">Recent</string>