Core improvements

Core improvements

    Major features:
      * Implement updates
      * Make sure we can advance RNGs from zero as well
      * Fix a problem with predictable descriptor
    Bugfixes:
      * Fix column mask inconsistencies
      * Fix a problem with partition key liveness info
    Quality of life improvements:
      * Get rid of driver dependency for query generation
      * Get rid of guava dependency
      * Add reusable config files
      * Switch from streams to iterables
    General improvements:
      * Make unset and nil descriptors more distinct and harder to generate particularly for the smaller descriptors
      * Fixed schema configurator to allow empty column sets
      * Move workloads to a common dir
      * Fixed schema configurator to output correct json
      * No-op checker to execute with Quorum, not ALL
      * Make tag for build unique

Patch by Alex Petrov for CASSANDRA-16262