model: update URI handling

* handle SIP URIs as objects instead of strings
* avoid many back and forth conversions between Uris and Strings
* update model after adding to contacts

Tuleap: #226
Change-Id: I0da6e36f9041ec675c0ee049692a3204a1ed6ac2
diff --git a/ring-android/app/src/main/res/values/strings.xml b/ring-android/app/src/main/res/values/strings.xml
index 6246ce7..a4796ab 100644
--- a/ring-android/app/src/main/res/values/strings.xml
+++ b/ring-android/app/src/main/res/values/strings.xml
@@ -136,5 +136,6 @@
     <string name="ab_action_speakerphone">Enable speaker</string>
     <string name="ab_action_contact_add">Add to contacts</string>
     <string name="ab_action_audio_call">Audio call</string>
+    <string name="share_via">Share via</string>
 
 </resources>