Fix arguments in method defifinition.

[graceful-potato]

Okay, I kind of fixed #135 , but I changed some other rules that I think I shouldn't have touched. I tried not to change them and do it using repositories for specific rules, but I noticed slightly different behavior when using repositories in vscode and textmate.

Before

After

Also I added double splat operator support in parameters.

[graceful-potato]

I can undo changes in punctuation.section.function, punctuation.section.array and punctuation.section.scope and instead create 1 more rule in main repository which will contain rules for braces, brackets and parentheses, but in this case I need help with naming.
I am not sure that this is a good scope name for braces and that this is a good name for parentheses. And also we need a scope name for brackets.

@infininight can you please take a look?