Merge pull request #170 from fredericbonjour/Admin

Updated Backoffice.
MySQL SchemaManager TABLE_CONSTRAINTS query optimization

In order to avoid full databases scan, constraints on the
TABLE_CONSTRAINTS table are moved from JOIN to query predicate.
Merge pull request #171 from franckstauffer/dev

MySQL SchemaManager TABLE_CONSTRAINTS query optimization
Prepared menu to be loaded from the server. Added categories for modules in the menu. Fixed localization. Added menu help.
Fixed menu help localization.