new index implementation draft

Change-Id: Ifda2f9a9e315d08c944732a4aa4bcc59cb3ca583
new index implementation draft

Change-Id: Ifda2f9a9e315d08c944732a4aa4bcc59cb3ca583
Merge branch 'bp/redesign-indexes' of https://github.com/dukhlov/magnetodb into bp/redesign-indexes
new index implementation draft

Change-Id: Ifda2f9a9e315d08c944732a4aa4bcc59cb3ca583
Merge branch 'bp/redesign-indexes' of https://github.com/dukhlov/magnetodb into bp/redesign-indexes

Conflicts:
	magnetodb/storage/impl/cassandra_impl.py
Merge branch 'bp/redesign-indexes' of https://github.com/dukhlov/magnetodb into bp/redesign-indexes

Conflicts:
	magnetodb/storage/impl/cassandra_impl.py
Merge branch 'bp/redesign-indexes' of https://github.com/dukhlov/magnetodb into bp/redesign-indexes

Conflicts:
	magnetodb/api/amz/dynamodb/action/create_table.py
	magnetodb/common/cassandra/io/geventreactor.py
	magnetodb/storage/impl/cassandra_impl.py
	magnetodb/storage/models.py
	magnetodb/tests/storage/test_cassandra_impl.py
	requirements.txt