TMDM-7900: "welcome page met err with db2 storage"

Adds DB2 to the databases that requires on-the-fly modification when a "=" is used on a CLOB column.
(https://jira.talendforge.org/browse/TMDM-7900)
TMDM-7766 : Add one column of message window for showing image status&recycle bin also showing image status&modify message content
TMDM-7760: revert https://github.com/Talend/tmdm-server-se/commit/6f43e6daf9039c2f8f79b25fd410b5773822b37e for TMDM-7911
Merge branch 'maintenance/5.6'