RCFilters: Move parameter operations to ViewModel

RCFilters: Move parameter operations to ViewModel

Refactor the operation of the model to work with parameters. Since we
work with parameters, there's no need to display and store the entire
state but rather only the active parameters -- which is the same operation
that the URL is displaying.

* Make sure that all controllers (Controller and UriProcessor) adhere to
  FiltersModel operation of minimization.
* Allow the FiltersViewModel to accept a parameter state to update itself.
* Simplify the operation of getting defaults and checking whether defaults
  are empty.
* Make sure that the storage construct (split to params/highlights) does
  not leak out of the saved queries model, the only place where it is
  relevant.
* Add unit tests and correct existing unit tests.

Change-Id: Icec513c94630314e7873f9ffe27779cd39150713