Add tests for splitintolines util.
Tighten up splitintolines tests.
Whitespace.
Add documentation for multibyte character handling.
Add preserveNewLines option to preserve newlines.
Document preserveNewLines option.
Rename 'include' option to 'columns'.

Keep include around as an alias so as to not break compatibility, also
might make more semantic sense depending on usage circumstances.
Support columnifying vanilla objects.

Split into array of kv pairs, make column headers configurable..