Modified implementation of DataTypeManagerService due to interface update
Includes TestParser class
TEIID-2808: Small fixes to unit tests and accompanying classes

* TestParser
 * Removes extraneous code
 * Makes the test expected objects consistent with actual objects

* Block
 * Mistake in equals method checking exceptionGroup against itself rather
   than other.exceptionGroup

* ElementSymbol
 * Type of element symbol not being checked in equals method
Updates to conform with spi

* Removal of tests to test plugin