Changed the label "community" to "marketplace
More translation conversions, fixed tests
Added missing admin translation back
Move transactions doc under service dir
Gateway fields
Remove payment_gateway from gateway_fields
Merge pull request #697 from sharetribe/update-transaction-doc

Update transaction doc
Merge pull request #692 from sharetribe/community-to-marketplace

Changed the label "community" to "marketplace
Add payment gateway to transactions with validations
Paypal urls and :none pgw type
Move transaction create logic to transaction service
Migrate data