PE-1632 - Added comment length checking to the parser.

Extended the ExpectedExceptionTester to ExpectedSqlErrorTester which can
be used to verify SQL error codes (ErrorInfo) carried by our exceptions.
Merge branch 'master' of git@github.com:Tesora/tesora-dve-pub.git
Moved assertError logic from PETest into PETest.ExpectedSqlErrorTester
which also asserts the exceptions.
Cleanup assertError code.