Added the external code coverage for Scrutinizer
Added the scrutinizer badges

[ci skip]
Fixed url of the Travis badge

[ci skip]
Added a safeguard against accessing the response without doing a request
Added support of any BrowserKit client with BrowserKit 2.3+
Added support of all BrowserKit implementation using filterRequest as well
Merge pull request #46 from stof/browserkit_response

Added support of any BrowserKit client with BrowserKit 2.3+