contactslist: improve UI/UX/behaviour

- replace the phone icon on the main activity by a magnifying glass
- allow the predicate to find contacts without phone numbers
- remove the autocorrect when finding a contact
- adjust contact search layout to be pushed by the soft keyboard
- hide the contextual menu (Scan QR and clear history) when in contacts
 mode.

This display of the searchview has not been improved since its gra-
phical behaviour may become inconsistent on some APIs.

Change-Id: Iea196eda67e62a9be94d6dfa3048b93921d0c4fd
Tuleap: #615
diff --git a/ring-android/app/src/main/AndroidManifest.xml b/ring-android/app/src/main/AndroidManifest.xml
index 45c3e23..06a0cae 100644
--- a/ring-android/app/src/main/AndroidManifest.xml
+++ b/ring-android/app/src/main/AndroidManifest.xml
@@ -80,7 +80,7 @@
             android:label="@string/title_activity_sflphone_home"
             android:screenOrientation="portrait"
             android:theme="@style/AppThemeWithOverlay"
-            android:windowSoftInputMode="adjustPan"
+            android:windowSoftInputMode="adjustResize"
             android:launchMode="singleTask">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />