New Go File is not valid

[2bitProgammer]

As of alpha#92

If I try to right click on a dir in my project and do New > Go File and try to create a file of name Foo.go it will error saying

'foo.go' is not a valid Go file name

If I change it to just foo it works fine. The error is not intuitive that it's trying to automatically append the .go extension to the file name. Also, it should be smart enough to know that if you append the .go to just roll with it.

[dlsniper]

I'll take a stab at this and do it before the next alpha