Finally deciding to move things into a proper license; which I can do
since I've never accepted (or had :( ) a pull request from another
person

This renames several interfaces that had names like IWhatever, since
that isn't a style that Java uses

This adds a new interface IFreezable, which denotes that your object
supports being 'frozen' (immutable) or 'thawed' (mutable). There is also
optional support for 'deep-freezing' objects, which disables the ability
to thaw them.

It also introduces a new exception called ObjectFrozen, which
implementations of IFreezable may or may not throw when you attempt to
modify a frozen object