ilike_operator removed

We do not use MySQL any more.
Return statements removed and some simplifications done.
"Cast" parsed URI to Boolean to avoid an explicit return of true.
Extra script to start sidekiq.
Replace shellscript shell by sidekiq process.
Merge pull request #653 from ontohub/external-sidekiq-start-script

Extra script to start sidekiq.
Merge pull request #647 from ontohub/refactoring_return-statements

Some simplifications
change type of iri fields to text

Of course if an iri-field for 255 chars
is too short in the alternative_iris tables it is
too short for every table. So this changes the type
to text for all remaining tables which contain an
iri field.
add support for ssh access on public repositories.
fix entitytest for text-iri field.
Merge branch '534-change_iri_type_for_all_tables' into develop
Merge branch '656-push_to_public_writeable_repositories' into develop