Joker-broker

* Toolkit, Toolkit._get_resource_broker
* rename Toolbox to StandardToolkit (aliased Toolbox for backward compat.)
* deprecate form='p', use 'r' instead

* change default conf path ~/.joker/broker/resources.yml
* remove lite section in in default conf

* Toolbox: do not close session in `__delete__` if created with external session passed in `__init__`
* DeclBase.create_all_tables: not allowed in non-abstract models
* DeclBase.find: rollback on error
* fix: FakeRedis has no attrib _db_num; rename redis_.py => redis.py
* use yaml.safe_load
* commit_or_rollback: do not close session
* rename redis_.py to redis.py
* remove rb.lite

* refactor: `ResourceBroker` is less verbose

* primary interface is not compulsory now

* add `Toolbox.bulk_insert`
* remove `j.b.default.locate_standard_conf`