* Solving postgres marshal/unmarshal issue
Postgres datastore was not marshaling the App config during its insert, that behavior was resulting in issues when fetching the App and the datastore couldn't unmarshal the config.
The same issue was probably happening with the Route's headers in some situations.
This commit's idea is to always try to marshal configs and headers when inserting/updating Apps or Routes. But in Apps and Routes get methods, if the config/headers unmarshal fails, it returns an empty config/headers.
* fix one more unmarshal case
* returning error when unmarshaling non-empty
* Make datastore tests pass with remote Docker containers
* Make tests consume DOCKER_HOST IP address as bind host while constucting database URI.
This fix makes datastore tests pass against
remote Docker (with host IP different from 127.0.0.1)
Fixes: #586
* Make datastore tests pass on Go1.7.1
* add datastore validator; adapt mock and tests
* adapt bolt datastore to common validator
* adapt postgres datastore to validator
* adapt redis datastore to common validator
* functions: modify datastore to accomodate hot containers support
* functions: protocol between functions and hot containers
* functions: add hot containers clockwork
* fn: add hot containers support
