Added python binding

Implemented classes:
 - elliptcis_proxy_t::remote
 - elliptcis_proxy_t::config

Example:
>>> from elliptics_proxy import *
>>> r = remote('localhost', 1025)
>>> c = config()
>>> c.remotes.append(r)
>>> c.groups.append(1)
>>> print c
remotes = [localhost:1025:2] groups = [1]
Added most functions of elliptics-proxy to binding

Implemented classes:
 - dned_id
 - key_t
 - lookup_result_t
 - data_container_t
 - async_read_result_t
 - async_write_result_t
 - async_remove_result_t
 - elliptics_proxy_t

Implemented functions of elliptics_proxy_t:
 - lookup
 - read
 - write
 - remove
 - range_get
 - bulk_read
 - lookup_addr
 - bulk_write
 - exec_script
 - read_async

and most of them was tested
Added the rest of methods of elliptics-proxy to python binding

Implemented class:
 - status_result_t

Implemented functions of elliptics_proxy_t:
 - write_async
 - remove_async
 - ping
 - stat_log
 - get_symmetric_groups
 - get_bad_groups
 - get_all_groups
Improved interface of python binding

You can use string instead of key_t to set a key
You can use string instead of data_container_t to set a dc
key_t and data_container_t can be used as before
Added enum SUCCESS_COPIES_TYPE to python binding

Using:
sa = success_copies_type.any