Revert "travis: fail if not clang-formatted"
Revert "travis: fail if not clang-formatted"

travis uses an ancient Ubuntu which does not even have the old
clang-format-3.7 yet

This reverts commit 41bff8184663d8bb41f318ba74f606f4c41fa667.

mamazu/tyroxx-blog-generator,TyRoXx/tyroxx-blog-generator,mamazu/tyroxx-blog-generator,TyRoXx/tyroxx-blog-generator