removed Next() call from docs in favor for .Get()
Merge pull request #7 from iron-io/long-polling

added long polling support to .Get() method for IronMQ interface.
change signature of Get method
Merge branch 'long-polling' into v3

Conflicts:
	README.md
	src/Demo.IronSharp/Program.cs
Merge branch 'v3' of github.com:pyeremenko/iron_dotnet into v3