Removed the `Dbal` prefix from the class names and moved them to the `Doctrine\Tests\DBAL` namespace.

1. XSD location pointing to the vendored file.
2. Removed `backupGlobals="false"`.
3. Added `failOnRisky="true" failOnWarning="true"`.
4. Added `beStrictAboutOutputDuringTests="true" beStrictAboutTodoAnnotatedTests="true"`.
5. Added code coverage whitelist.

I am not sure if there is a rationale behind ignoring extra keys like
this. I was under the impression that something might copy options to
platform specific options, thus leaving options in the original array,
knowing they would be ignored anyway. If it is the case, it would be
best to just move them, otherwise, this commit might help troubleshoot
some mapping issues.
I had to fix some tests that wrongly used that options array (maybe
these options were valid at some point?).

Add DbalPerformanceTestListener to collect & report performance test timing results.

Remove AllTests approach to PHPUnit and work with a phpunit.xml.dist from the top level of the repository.

[2.0] Solved the hassle with dropping/creating the test database through introducing a second test database for temporary connections. Please check the dbproperties.xml.dev file for reference. The 2 test databases need to be created *once* before the very first time of running the tests. New procedure successfully tested against mysql, postgresql, oracle.

First tests for basic collection implementation. First experimental use of closures (Currently commented out, because the svn server makes a syntax check against 5.2.x).