Minor snippets improvements

Created by: pdf

Since the ace editor is already available for online editing, it should be added for snippets too (indentation is pretty painful without it).

It would be nice if there was a way to get a download link that includes the file name (I assume this is why the field exists, but I can't see it used anywhere). This link could be at snippets/:id/raw/:file_name maybe...

Those are the simple changes, then there's versioning, but that a whole other kettle of fish...