Moved to XCTest and updated to recommended project settings.
Fixes for several compiler warnings:

-Wimplicit-atomic-properties
-Wsign-conversion
-Wreceiver-is-weak
suppress -Wformat-nonliteral warning
Merge pull request #36 from Liffft/xctest

Moved to XCTest and updated to recommended project settings.
Merge pull request #37 from realestate-com-au/fix-minor-warnings

Fixes for several compiler warnings
Fixed regression passing the namespace key
Updated podspec for 1.5.1