Add support for the GDScript language

[fingolfin]

References:

• https://github.com/okamstudio/godot/wiki/gdscript
• http://www.godotengine.org/

Some projects using it:

• https://github.com/okamstudio/godot
• https://github.com/Qwertie-/Godot-games

My motivation for adding it: To disambiguate these .gd files from GAP .gd files.

[pchaigno]

The Travis build fails because the Bayesian classifier doesn't have the values for GDScript.
Try to regenerate the samples: bundle exec rake samples

[fingolfin]

Done. I thought I read somewhere that I should not commit the sample.json file, to avoid merge conflicts, hence I left it out (but I did regenerate it locally and also run the tests).

[pchaigno]

That was probably me.
I usually recommend to not commit the samples.json when possible.

[fingolfin]

Hm, I wonder why samples.json is in the repository at all, then -- isn't it normally "best practice" to avoid committing generated files (for multiple reasons, one of them being the wish to avoid silly merge issues)? That would require people using the linguist repo to run bundle exec rake samples manually, but that wouldn't be too hard, would it? In other projects, I would probably have a build rule in my Makefile for it anyway, so that I (and others) never can forget to regenerate it. That said, I am not very familiar with ruby resp. Rakefiles, and I guess you have your reasons... just wondering... :)

[pchaigno]

@fingolfin Good question...
@arfon @bkeepers Do you know why the samples.json file is not in .gitignore as @fingolfin suggested?

[bkeepers]

That's a great question. @tnm do you know?

I don't know enough of the history on this project to say if there's a reason to have it committed.

[arfon]

The Bayesian classifier needs it!

[arfon]

The Bayesian classifier needs it!

Oops, my bad for reading this on my phone and not seeing the earlier context.

FWIW I agree this flow is less-than-optimal right now. Perhaps we should just add a bundle exec rake samples to the .travis.yml file to ensure that builds don't fail because of outdated samples?

[arfon]

BTW this PR goes some way to improving this situation.