Improvements to Split block for whitespace and lines:

* Split by whitespace now uses the built-in definition of whitespace \s
  This catches all characters definted as whitespace, see below:
  https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp
* Split a line by all unicode compliant line breaks. The biggest impact here is
  that OSX and Windows files will now split the same way.
The cr option is still around, but ther's no longer a need for it, IMO.
Merge in recent changes (split block improvements #619)
Merge pull request #619 from cycomachead/split

Improvements to Split block for whitespace and line options