Organize CDDL

We need to:

* add proper bounded types that can be reused `uint64`, `unit32`, ... `int64`, `int32`, .... `pint64` (positive), etc. as well as other reusable types that are not part of cddl
* place all the types that are used throughout many eras into `cardano-ledger-core/cddl-files`
* Extract types that are not fully representable (eg, unit_interval) into separate `test.cddl` files and assign a bunch of valid random data, so instead of generating from an invalid range generator will just pick valid values. A separate file will contain the representation for such type to the extent that CDDL is capable of specifying them