Add upper()/lower() functions
Add SHOW TABLES
Merge pull request #76 from testn/master

Add upper/lower function and show table command
tweaks to upper/lower and misc removal of unused imports
Switch decimal arithmetic tests to become unit test.
Remove unused methods.
Rename a test class.
Rename a test class.
Merge pull request #97 from tonyhuang/scale

Refactor Decimal Arithmetic Tests to be unit tests.