Modified politer to be a class instead of a function, allowing it to have a
bunch more useful methods. Second try at the TextList problem!
Finished the politer rewrite. Fixed a bug in quoted_chars.
Rewrote regex_branch completely. Added Politer.pop(), popped().

Several functions were cleaned up with politer methods and/or concat().
Fixed a bug in Politer.send. More cleanup.
Added back the politer() function. Like iter(), it will return the original
object if it is already a politer.
The next run at the TextList setup. Better in some ways with the new politer,
but still problematic and doesn't work. Big class solution is probably
not the right approach.