Add tests

Hilib is a concatination of several libs (helpers, managers, mixins,
views). Helpers, managers and mixins already had tests, but I did not add them
to hilib yet. Tests for views have to be written.
Add caching to view manager

Every view has a flag options.cache which is true by default. With
caching, the view is stored in a hash with a hashCode as key and the
view as value.
empty commit