add new queue for priority pushes.
add rules for priority-push to settings.yml

See information about the rules here:
https://github.com/ontohub/ontohub/issues/694#issue-27703382.
add specific queue handling to batch worker

The OntologyBatchParseWorker now can take method calls which directly
supply the queue to place the job in. Additionally there is a convience
method for the priority-push queue.
add methods for priority-conditions check

Add a method to check whether the necessary priority
conditions are met. Additionally add a helper
method to retrieve the specific settings.
send batch-parse jobs to priority if appropriate.
handle priority for batch-parse correctly.
add specs for batch parsing and adjust old ones.
fix calls for batch parsing in priority.
add future-job specs for batch-parsing

Add specs to ensure that future jobs (concurrency balancing) will stay
on the queue they started out at (with the exception of the sequential
jobs, which have their own queue).
add suspended-save ontology spec for priority

In the case of small pushes suspended_save_ontologies
should create the jobs accordingly.
remove deprecation warning in git-repo-spec

The deprecation warnings with regard to be_true
have been turned into be(true).
obey hound.
use nicer rspec-mock (allow_any_instance)

Per eugens 'suggestion' i'll use allow_any_instance
and the receive mocker.
add spec for push with big commit

Per eugens suggestion we will now test every bound of the 'small push
priority'-system.
add start/stop rake task for hets server.
support invoker for managing hets.
add mime-router and grouped constraints

MIME-Router will allow to filter based on mime-accepts-header
and GroupedConstraint will allow to include multiple Constraint
in an 'and' fashion (all constraints need to be return true).
handle iri for html and plain

In the html-case just perform show action.
In the plain case send the ontology-file as download.
replace mixed iri/download link two links

The iri link (which displays the iri of an ontology)
now actually links to the iri. And the download-link
has moved as a button next to the evaluate button.
add basic classes to call hets-api.