Smart Query standalone test applications

Wide test coverage is crucial for smart query development. Building a couple of standalone test applications, rather than prototyping inside MaxScale.

• Test app to exercise smart query heuristics and benchmarking hand written smart routing rules.
• Sql generator that generates a mix of queries that fall into both column, row and in-between categories.
  Logging hours to this Jira for building the apps. The heuristics, routing, rules etc. that correspond to prototyping are logged to MXS-2281, Smart Query build prototype.