Start changing elliiptics python api
Merge branch 'master' of github.com:reverbrain/elliptics into python

Conflicts:
	bindings/python/elliptics_python.cpp
Fixed new API
Added extra namespace for python binding. Moved elliptics_id into separated files.
Moved async_result and elliptics_time from python binding to separated sources.
Moved elliptics_session in separated sources.
Added elliptics python package with __init__.py. Renamed boost::python elliptics module to core and moved under elliptics package. Removed unnecessary setup.py in bindings.
Added RouteList and draft of Session.
Added node.py.
Added transform to session for calculating checksum of data. Added exceptions_policy to python binding
Added namespace to python binding
Added user flags to python binding
Added timestamp setter and getter to python binding. Added now() to elliptics.Time
Added timeout to python binding
Extended ReadResultEntry in python binding
Added read_data_from_groups, write_data_by_chunks
Extended LookupResultEntry
Fixed python style errors.
Added connect ability to python AsyncResults. Added convert_to_list method. Extended LookupResultEntry.storage_address: now returns route.Address intead of string. Added write_cas and write_cas_callback to python session.
Added write_prepare, write_plain, write_commit to python binding.