Removed duplicate web-profiler mounting

https://github.com/silexphp/Silex-WebProfiler/blob/master/WebProfilerServiceProvider.php#L207
bug #23 Removed duplicate web-profiler mounting (nkt)

This PR was merged into the 1.1.x-dev branch.

Discussion
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Removed duplicate web-profiler mounting

https://github.com/silexphp/Silex-WebProfiler/blob/master/WebProfilerServiceProvider.php#L207

Commits
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8065e55 Removed duplicate web-profiler mounting