Once the Microsoft SQL Server Native PHP Driver has been committed (see
MDL-15093), we need to integrate it with Moodle 2.0. I implies, at least:
- add "sqlsrv" (version 9) to 2.0 environment.xml file
- enable "sqlsrv" in install.php and check everything works (new lang strings, perhaps?)
- modify any conditional use of get_dbtype() (we shouldn't have any) if necessary.