Remove sensio connect signup functionality

```
➜  KnpBundles git:(remove-sensio-connect) ✗ phpunit -c app
PHPUnit 3.7.37 by Sebastian Bergmann.

Configuration read from app/phpunit.xml.dist

........................................

Time: 3.03 seconds, Memory: 40.50Mb

OK (40 tests, 95 assertions)
```

```
➜  KnpBundles git:(remove-sensio-connect) ✗ ./bin/behat @KnpBundlesBundle          
...................................................................... 70
...................................................................... 140
...................................................................... 210
...................................................................... 280
.....................................................................

54 scenarios (54 passed)
349 steps (349 passed)
1m10.152s
```