style/consistency fixes

This PR includes style/consistency fixes for the easyconfig included in https://github.com/hpcugent/easybuild-easyconfigs/pull/385, and related easyconfigs.

@tovrstra: Please review this, and merge it in unless you have remarks/questions, so it gets included in https://github.com/hpcugent/easybuild-easyconfigs/pull/385. I think after the merge there are one or two open questions for you in that PR.

I'll also test all the builds on our end, and will report on problems (if any) in PR https://github.com/hpcugent/easybuild-easyconfigs/pull/385.