Initial commit of splitToWidth method

Uses built-in LineWrapper with dummy document
Updated to more accurately reflect doc.text
Add saveFont and restoreFont methods

Behaves similarly to save() and restore()
Move splitToWidth into separate file
textMap initial commit

Add option to have doc.text make a “textMap” object that describes how
it breaks a block of text, and where each word/line exists on the page.
Renamed require file to 'text_map'
Support (untested) for page breaks