Tfs build plugin

Based also on the work done by @pombeirP for TeamCity...

At the moment, it works for me...

States are shared with #2166...

Contrary to TeamCity and Jenkins, there is no web api shared by a TFS server :(

That's why I have created 2 projects that use the tfs assemblies for the 2 version of Visual Studio that support a TFS(Git) repository...

PS : Perhaps, you won't be able to build these project because the tfs assemblies are needed (installed with Visual Studio or [Team Explorer for Microsoft Visual Studio](http://www.microsoft.com/en-us/download/details.aspx?id=40776) ) I wonder if I should better build these assemblies and add the dlls in references. What do you think about that?