Industrialization: pool has workers, config has profiles

* pool.py: added Worker(Thread) class
* pool.py: added Mem class as shmem for crawlers assigned to the same
entry_point
* pool.py: notation changed: crawler is function without context, worker
is crawler, assigned to entry_point, having period and (pointer to)
shared memory
* pool.py: added try ... catch clauses for robustness
* pool.py: added logging on info. error and debug levels
* config.py: moved almost everything from py to json
* runtime.json: new structure with profiles
* utils.py: removed logging from call_throttler as function.__name__ is
undefined for partial()
* crawlers_new/: sandbox for testing, to clean-up
Industrialization: removed explicit api from vk, crawlers as functions, gentle exceptions and logs

* config.json: new name for runtime.json
* config.py: added logging facilities
* config.py: replaced __data with __defaults
* pool.py: fixed bug of always non-equal sets of workers (added __eq__)
* pool.py: fixed bug of joining not started threads
* pool.py: more gentle exception mechanism
* vk.py: removed explicit api definition, any call is avl from client's
code
* vk.py: added refresh method, called by pool
* vk.py: call_throttler period is now can be changed dynamically in
config.json
* vk.py: new wrapper users_get_unlim to hide the implementation of
splitted calls of users.get
* vk.py: more gentle exception handling, including vk errors in
responses
* crawlers_new/crawlers_main.py: all (3) crawlers have been migrated
into simplified form

TODO: add mongodb dump of json objects directly from vk module
Mongodb dump, hide config.json, crawlers cleanup

* vk.py: added mongodb dump
* config.py: config file can be set at runtime
* old crawlers are moved to crawlers_old/; crawlers_new/ renamed to
crawlers/
* new crawlers: ep_online, first_circle_online
* run.py: is new startup file; startup code has been removed from
pool.py
* code cleanup: removed unused imports and functions from utils.py
Delete config.json