Various procedure/function related fixes for EPAS/PG 11. Fixes #3446

- Fix the RM #3446 "plpgsql keyword should displayed in SQL pane for EPAS-11".
- Procedures for EPAS 11 always created as 'edbspl', even though language is sql or plpgsql.
- Not able to create Function/Procedure/Trigger function if the language is "C" for all supported database server.
- Function creation for EPAS 9.6 and above when set "Window?" flag to "Yes".
- Disable Volatility, Strict, Parallel, Estimated cost and Leak prof while creating procedures in EPAS 11 when language is not 'edbspl'.
- Rename "default" folder to "11_plus" inside "pg" directory for procedures, as procedures are supported from PG11 onwards.
- Creating/Deleting parameter in Procedure for PG 11.
- Drop procedures with arguments for PG/EPAS 11.
pg_proc table has added default value 'v' for Volatility, 100 for Cost and 'u' for Parallel for any language. All the three are not supported for Procedures in PG/EPAS 11 (excluding 'edbspl' language for EPAS). Fixed the issue where it is visible in properties panel if we create procedure using language 'plpgsql' or 'sql'.

docs/en_US/release_notes_3_2.rst

@@ -22,4 +22,5 @@ Bug fixes
 | `Bug #3319 <https://redmine.postgresql.org/issues/3319>`_ - Cleanup and fix handling of Query Tool Cancel button status.
 | `Bug #3363 <https://redmine.postgresql.org/issues/3363>`_ - Fix restoring of restore options for sections.
 | `Bug #3371 <https://redmine.postgresql.org/issues/3371>`_ - Don't create a session when the /misc/ping test endpoint is called.
+| `Bug #3446 <https://redmine.postgresql.org/issues/3446>`_ - Various procedure/function related fixes for EPAS/PG 11.
 | `Bug #3457 <https://redmine.postgresql.org/issues/3457>`_ - Fix debugging of procedures in EPAS packages.