change routings in payment flow
free_transactions still needs to point to listing_conversations views
added new-function to braintree transactions flow
removed unused new_conversation function
start different payment processes
renamed free transactions to 'free and checkout transactions'
from payment service separation to payment process separation
separated free transactions from post-pay transactions
refactoring: more explicit post pay status
Merge pull request #629 from sharetribe/separate-payment-processes

Separate payment processes