Add Generator and related classes for Db2.
Add tests for Db2 generator and associated classes.
Add Db2 processor and factories.
Add tests for the Db2 Processor.
Adds a readme file with release notes for DB2 support. Neatened up the DB2 generator classes.
Merge pull request #521 from jrackley/Db2Support

  Adds a readme file with release notes for DB2 support. Neatened up the DB2 generator classes.
  Add tests for the Db2 Processor.
  Add Db2 processor and factories.
  Add tests for Db2 generator and associated classes.
  Add Generator and related classes for Db2.