Merge pull request #30 from pitr-ch/refactor

Sequel adapter, querying
Merge pull request #31 from pitr-ch/refactor

Algebrick 0.2, RemoteViaSocket executor, Daemon, graceful shutdown, logging
Fix sequel migration

Due to mixing order of the uuid and id on various places, there were
issues such as:

     DETAIL: Key columns "execution_plan_uuid" and "id" are of
     incompatible types: character and integer.

Basically, it tried to map the uuid to action id and vice-verse.
Merge pull request #32 from iNecas/fix-sequel-migration

Fix sequel migration
Run plan phase in transaction

And active_record transaction driver
Make sure we pass symbol to order_by

Postresql is sensitive about that.
Don't use the original exception for step#error

Use our own class instead. There were issues with
serializing/deserializing of the exceptions.
It should send only Dynflow::Error over

fall down to FATAL when something else is risen
Add missing r/w barrier to @socket in RemoteViaSocket

fixes occasional nil error, due to missing socket