Started refactoring connection code
Added more change
Started replacing connection pool
More work on adding new connection pool, still using gocql's connection pool for now
Fixed arg type
Tidied up cursor and connection code and improved support for concurrent query execution
Changed internal session structure an added Runnable interface
Added new connection pool
Changed API for max idle/open conns
Fixed imports
Fixed some issues
Some small performance improvements
More fixes
Readded recovers
Updated documentation for connection pools and added the IdleTimeout parameter
Tidied up cursor
Merge branch 'feature/tidy_connections' into develop