Support New "Job Hook" Hook Renaming

[armsnyder]

closes #130

Validated by sending a test event from GitLab and it works.

[gmessner]

@armsnyder
First off thank you for your contribution and this certainly needs to be fixed. The fix looks good other than the name choice for:

 public static final String X_GITLAB_EVENT = "Build Hook";
 public static final String X_GITLAB_EVENT_2 = "Job Hook";

I'd like these to be a bit more descriptive since there is no longer a one to one relationship, could you change these to the following?

 public static final String BUILD_HOOK_X_GITLAB_EVENT = "Build Hook";
 public static final String JOB_HOOK_X_GITLAB_EVENT = "Job Hook";

[armsnyder]

Absolutely. I'll throw in a comment as well since even that change doesn't fully explain what's going on.

[gmessner]

@armsnyder
Thanks for making the changes. I've merged the PR, will do a release sometime later this week, have a few other changes that need to go in before the release.