- added print(char) API
   - added unit test to validate create 12

unit-tests checking that chectime() can terminate contracts in the middle of hashing intrinsics #3255

- all ram trading fees sent from user to eosio.ramfee (also implement 1% fee Fix #3182)
- all tokens received for ram sent to eosio.ram
- all proceeds from selling ram sent from eosio.ram
- all staked tokens sent to eosio.stake
- all unstaked tokens sent from eosio.stake
- fix build dependency issue with ram_tests

cancel_deferred returns 0 (transaction not found) or 1 (canceled), don't reset refund timer when taking moner from refund to stake #3180

get_error_message now returns safer optional<string> even though it may introduce unnecessary copies; find_error_message no longer necessary