Use ConsoleIO for output
Use ConsoleIO for output

Using plain `echo` means we still generate output when running `composer install --quiet`.

Simple fix is to use the IO class from the Event (had to pass it to executeBuildBootstrap too for that purpose).

sensiolabs/SensioDistributionBundle,HeahDude/SensioDistributionBundle,HeahDude/SensioDistributionBundle,sensiolabs/SensioDistributionBundle