add visual studio 2013 fsharp project template

Microsoft Visual Studio Premium 2013
Version 12.0.21005.1 REL
Microsoft .NET Framework
Version 4.5.51641

Installed Version: Premium

Visual F# 2013   06191-004-0456024-02825
Microsoft Visual F# 2013
Merge pull request #277 from enricosada/vs2013_templates

add visual studio 2013 fsharp project template