TelephonyImpl added

Implemented Telephony Interface
NetworkReachabilityImpl added

Implemented NetworkReachability interface
MessagingImpl added

Implemented Messaging Interface
DeviceImpl added

Implemented Device Interface
Added CapabilitiesImpl

Implemented the HasSensorSupport method for Capabilities interface
Project File changes

Added new created files
Added ContactImpl

Implemented Contact API interface, Windows Phone 8.1
Revert "Project File changes"

This reverts commit 0c0e7a5875047ff156228de32466223b0c66e1a6.
Merge remote-tracking branch 'upstream/master'
Merge pull request #5 from Aryslan/master

Windows Phone 8.1 APIs added