[11155] Provide way define UNIX_TIMESTAMP/FROM_UNIXTIME for PosgreSQL users.

If mangos build for use Postgre SQL server
Queries from sql/postgre_compatibility_addon.sql must be used
at least one time for each mangos DB part stored in Postgre SQL server.

File constent based at article in http://janusz.slota.name/blog/

Signed-off-by: VladimirMangos <vladimir@getmangos.com>

sql/postgre_compatibility_addon.sql

@@ -0,0 +1,22 @@
+-- This queries for users PostgreSQL.
+--
+-- Its need apply single time after DB creating or later (safe reapply)
+-- and let correctly execute SQL queries with UNIX_TIMESTAMP/FROM_UNIXTIME
+-- functions uses in mangosd/realmd code.
+
+-- NOTE: Queries must be applied to each mangos DB parts: mangos, characters, realmd at least one time.
+
+-- no params
+CREATE OR REPLACE FUNCTION unix_timestamp() RETURNS bigint AS '
+	SELECT EXTRACT(EPOCH FROM CURRENT_TIMESTAMP(0))::bigint AS result;
+' LANGUAGE 'SQL';
+
+-- timestamp without time zone (i.e. 1973-11-29 21:33:09)
+CREATE OR REPLACE FUNCTION unix_timestamp(timestamp) RETURNS bigint AS '
+	SELECT EXTRACT(EPOCH FROM $1)::bigint AS result;
+' LANGUAGE 'SQL';
+
+-- timestamp with time zone (i.e. 1973-11-29 21:33:09+01)
+CREATE OR REPLACE FUNCTION unix_timestamp(timestamp WITH time zone) RETURNS bigint AS '
+	SELECT EXTRACT(EPOCH FROM $1)::bigint AS result;
+' LANGUAGE 'SQL';

src/shared/revision_nr.h

@@ -1,4 +1,4 @@
 #ifndef __REVISION_NR_H__
 #define __REVISION_NR_H__
- #define REVISION_NR "11154"
+ #define REVISION_NR "11155"
 #endif // __REVISION_NR_H__