Improve Split regex

[smartycope]

Added negative and * indecies and quotes to Split parameters

[michaelmior]

Could you clarify what the purpose is of the changes to the split regex?

[smartycope]

It does a few things:

• Allows you to split on spaces and commas by using quotes
• Allows for negative indexing on the split
• Allows you to return all the split items as a list, instead of having to select a specific index
• The regex now allows for optional whitespace between the arguments (just to make the extension a little more pythonic)

[michaelmior]

@smartycope Thanks! I think it would help to have pieces of the regex documented in the code since it's non-trivial to understand.

I'm also curious why you used (?:\s+)? instead of (?:\s*). Is there some subtle difference I'm missing?

[smartycope]

@michaelmior I added the documentation you asked for, good thinking.

As for (?:\s+)? vs (?:\s*), I don't know of a difference, that's simply how it was generated.

[michaelmior]

LGTM, thanks!