Added contacts usage description

Author: hugobgranja

plugin.xml

@@ -55,6 +55,12 @@
     <config-file target="*-Info.plist" parent="NSCalendarsUsageDescription">
       <string>$CALENDAR_USAGE_DESCRIPTION</string>
     </config-file>
+    <!-- Usage description for Contacts needed in some iOS versions when searching 
+      for locations and invitees using the interactive mode  -->
+    <preference name="CONTACTS_USAGE_DESCRIPTION" default=" " />
+    <config-file target="*-Info.plist" parent="NSContactsUsageDescription">
+      <string>$CONTACTS_USAGE_DESCRIPTION</string>
+    </config-file>
     <header-file src="src/ios/Calendar.h"/>
     <source-file src="src/ios/Calendar.m"/>
     <framework src="EventKit.framework"/>