Create a dictionary collection and a dictionary factory.

The dictionary collection is a class complying to the Dictionary
interface that acts as a front end to a collection of arbitrarily many
dictionaries of any type.
The dictionary factory is a helper class for creating various
dictionaries and get some meta information about them.

At the same time, this change makes the BinaryDictionary class
not a singleton any more.

This also needs I9afe61a9 to not break the build.

Change-Id: I61fdcc4867fcda18342807bf1865e6e46979e5d5