Added file diff into commit message

[Dragonn]

Added list of modified files into each commit message. Reused output of git status --porcelain.

Current log messages now looks like this:

commit 16c88f652928535e9d5a68750de4cfe746489335
Author: Katafygio <katafygio@localhost>
Date:   Fri Feb 1 07:31:20 2019 +0000

    Kubernetes cluster change
    
     M tech/configmap-gitlab-runner-cm.yaml
     M tech/deployment-gitlab-runner.yaml

Please review and possibly refactor my changes. I am not golang developer.

[coveralls]

Coverage remained the same at 89.651% when pulling cf7f1c8 on Dragonn:master into e6353dd on bpineau:master.

[bpineau]

Thanks @Dragonn . The Travis status reporting is currently broken (though builds are still triggered); could you please ensure make test pass?

[Dragonn]

Tried to fix that as good as I am able to. Please review changes.

Sorry for that force-push in history, I have some minor troubles with setting GPG and local git settings.

[bpineau]

Sorry for the late answer; I'm not sure about the use case for that, as the information is readily available in the commit anyway?
The git history (so repos size, so clone time) can grow quite fast on busy clusters; we should be careful when adding redundant information to commit messages.

[Dragonn]

This MR was primarily focused on usage by users not so familiar with git CLI (eg. browsing history in Gitlab or similar GUI) to be able to easily locate recent changes in their namespace.

I have discovered this behavior can be easily achieved by parameter git log --name-status, so currently I don't see any more point in this MR. I can imagine this behavior can suit to someone (e.g. when using GUI-only access), so maybe it could be implemented as opt-in parameter, but I am not going to implement it right now.

On the other hand I don't think size argument is valid here based on what I see in my clusters. Most commits are 2kB ~ 200kB, so cca 80B (per file, 4% in case of smallest commits) so I don't see much storage wastage.