Add a way to define various profiles

[robUx4]

Basic Matroska has 4 profiles, and each elements is defined within a range (minver/maxver). But what if an element skips a version (ie make a return in the future) ?

WebM can also be considered as a profile. And it has version too.

DivX may also be a particular profile.

We could define these profiles separately. And maybe the main Matroska ones as well. That may also be a way to extend values in a profile, to explain value in an element existed since value X of the profile.