merged in pr restsharp#737

Merge pull request restsharp#733 from restsharp/work_in_progress

new nuget targets and other cleanup

published a new nuget version

updated the nuget package

Merge branch 'master' of https://github.com/restsharp/RestSharp

Conflicts:
	.nuget/RestSharp.Build.dll

Updated version number