Merge pull request #359 from toddreifsteck/dev

[Xamarin.iOS] Fix duplicate registration bug in Xamarin iOS client
[client][managed][test] reduce memory footprint of .net45 test project and support running from console
[client][managed] fix warnings
Merge pull request #387 from hasankhan/warnings

[client][managed] fix warnings
Update CHANGELOG.md
Merge pull request #388 from hasankhan/autotest

[client][managed][test] reduce memory footprint of .net45 test project a...
Fix iOS push tests to follow updated payload format for APNS