Heap memory parameters are configurable now

Closes-Bug: #1364469
Change-Id: Id6383b5ed7b6841a6ecbc79f9ea4823f18c10c19
Adapt cassandra tox tests to the latest code

Implements: bp adapting-cassandra-tox-tests

Change-Id: If5eeee030adf5be9c15cdb9aec096eb6a40b07e3
Merge "Heap memory parameters are configurable now"
Merge "Adapt cassandra tox tests to the latest code"
Add queued storage manager

Change-Id: Ibcb05258f2644fac46c783f46429c0761f802744
Implements: async-shema-operations