Testsuite step2

**unit_test**
- progress in the filling of the unit test vector
- add bitcoin.transaction() support in unit test vector

**Integration test framework**
Integration test supports scenarios testing. To create a new scenario just add it in fixtures.py. 
For instance: https://github.com/JahPowerBit/counterpartyd/blob/testsuite/test/fixtures/fixtures.py#L326
and add it in the scenarios list:
https://github.com/JahPowerBit/counterpartyd/blob/testsuite/test/fixtures/fixtures.py#L367
it's possible to run test only for one (or several) scenario:
`py.test test/integration_test.py --scenario=scenario_1 --scenario=scenario_2`
scenarios are executed in sqlite memory database (20x faster)
For each scenario, the sql dump, and the logs are compared with fixtures:
https://github.com/JahPowerBit/counterpartyd/blob/testsuite/test/integration_test.py#L7
To generate fixtures when creating a scenario, use the save_scenario() function:
https://github.com/JahPowerBit/counterpartyd/blob/testsuite/test/util_test.py#L231

**next steps**
- books test: https://github.com/CounterpartyXCP/counterpartyd/issues/241
- rpc test: https://github.com/CounterpartyXCP/counterpartyd/issues/19
- finish filling of the unit test vector