cc: @gtribello

just annoying when there are directories whose name contains a space
within the src/ directory

see #227

Notice that without the fix this test fails.

backport of 4a96057e

thanks to @valsson

Check first if astyle is present. In this way, when astyle is not compiled,
we get a single error instead of one error per file.

Thanks @hanatok!

Also this after a discussion with @marcodelapierre

thanks to @marcodelapierre

This reverts commit 2128bada.

Giving false positive in master branch - no idea why and cannot debug it

This reverts commit 5ba9eb93.

More efficient on travis-ci