The cast to float needs to happen before the division, otherwise integer
division will be performed, and as a result `CLOCKS_PER_NSEC` will
always be 0 if `CLOCKS_PER_SEC` < `NSEC_PER_SEC`.
* Add utility functions to treat All as a heterogeneous container
* Distinguish RefC Int and Bits types
* Change RefC Integers to be arbitrary precision
* Add RefC Bits maths operations
* Make RefC div and mod Euclidean
* Add RefC bit-ops tests
* Add RefC integer comparison tests
* Add RefC IntN support
