Patch for pgScript

Hi pgadmin hackers,

First, let me wish you a very happy new year 2009.

Then, here is a patch for the pgScript part of pgAdmin:
Features:
- Use of pgAdmin UI to highlight the line where an error occurred
(frmQuery, pgsDriver, pgsThread, pgsApplication, pgsStmtList)
- Possibility to execute only one part of the script by selecting it (frmQuery)
- Changed output style (exceptions/*, expressions/pgsExecute,
statements/pgsStmtList)
- Improved the script for integration tests: it does not print the
executed queries anymore because the output was too messy
(xtra/pgscript/file/test/execute.sh)
Bugs:
- Fixed print statement which caused a lock in case an exception was
thrown (statement/pgsPrintStmt)

Best regards,
Mickael