Open to do actions for SQL::Statement 1.xx
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* re-add support for case-sensitive column names, either as typed in query
  or as known by the table
Open to do actions for SQL::Statement 2.xx
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* Rewrite Parser to use a grammar (e.g. like SQL::Translator::Parser)
  + Implement ANSI SQL grammar as default
  + Be flexible which grammars to use (as currently supported)
* Rewrite Statement handler to have command instances per command
  + Use sub-classes for different join behaviors to reduce flag
    comparing in inner loops
* Add Optimizer for conditions (constant first, ...)
* Add Sub-Select support