UPD re: SaaS cloud

• Externalise MIME type configuration mappings out of JCR config, use property-based configuration sources to facilitate mappings.
• consider personas that should have access to such configuration (consider Magnolia admins as the only ones initially).

Original description

Once the cached mime-types list is propagated from JCR it's impossible to reset it without hacks. This is in production not such a big issue, but it leaks in unit-tests. There are several classes which don't run isolated and are implicitly depending on other unit-tests to set up the JCR nodes underneath /server/MIMEMapping and load them using #init().

Apart from that:

• it's not using node2bean mechanism, instead it's directly accessing JCR. It should be aligned to other observed managers in server-config.
• It's not a util-class, it should not be static.