feature: allow tweeting bounties on creation

WIP: mostly done, still need tests and probably some fixes
fix: Catch None values for amount (i.e bounty relation is None)
Merge remote-tracking branch 'upstream/master'

Conflicts:
	bountyfulcoinsapp/forms.py
feat: add payment helper to receive payments

use bitcoinaddress client side wrapper

relates to story #66922784
fix: correct save buttons to work properly
tests: correct tests to above behavior
Merge pull request #16 from asfaltboy/payment_helper

Merge Feature: Payment helper