These make the hydra-queue-runner logs very noisy even when not using the GitlabStatus plugin.
Also, they shouldn't be necessary except when developing the plugin itself and should have been removed before release.
Plugins are now disabled at startup time unless there is some relevant
configuration in hydra.conf. This avoids hydra-notify having to do a
lot of redundant work (a lot of plugins did a lot of database queries
*before* deciding they were disabled).
Note: BitBucketStatus users will need to add 'enable_bitbucket_status
= 1' to hydra.conf.
Mutliple <githubstatus> sections are possible:
* jobs: regexp for jobs to match
* inputs: the input which corresponds to the github repo/rev whose
status we want to report. Can be repeated
* authorization: Verbatim contents of the Authorization header. See
https://developer.github.com/v3/#authentication.
