Throw a SourceControlException if there's a bad config.

Related to #722. When initializing a VBA repository, it's possible that the user hasn't set up a gitconfig yet. Rethrow our own standard exception for the situation to be handled in the UI layer.

Author: rubberduck203

Rubberduck.SourceControl/GitProvider.cs

@@ -152,7 +152,17 @@ public override IRepository InitVBAProject(string directory)
                     repo.Stage(stat.FilePath);
                 }
 
-                repo.Commit("Intial Commit");
+                //If the user hasn't set up their name, this could throw an exception.
+                //There may be other situations in which this could occur, but I'm not sure what they are right now.
+                //Todo: consider a more specific exception that inherits from SourceControlException.
+                try
+                {
+                    repo.Commit("Intial Commit");
+                }
+                catch(LibGit2SharpException ex)
+                {
+                    throw new SourceControlException("Unable to perform intial commit.", ex);
+                }
             }
 
             return repository;