Pointer on download link
No longer display GitHub dev version as download

Users can go to GitHub for this
Latest version is only recommended version
Upgrade to 4.0.3 and all DB types

As Adminer is now an optional plugin and no longer part of the main
ICEcoder dist, we can afford to offer the full Adminer package which
includes new DB types (MS SQL, PostgreSQL etc). In doing this also
upgraded to 4.0.3 (from 3.7.1)
Couple of new comments added