Use QDType bit interfaces for classical simulation

[anurudhp]

Final part of #1142!

• Remove classical sim ints_to_bits and bits_to_ints, and always use QDType bit interfaces (from_bits, to_bits etc.).
• Update all bookeeping bloqs to use the QDType bit features.

Fixes #811
Fixes #606
Fixes #643

[mpharrigan]

Since this will close all those bugs, can you open a bug for classical simulation of fixed point. A brief overview of the current situation where you pass around ints because of deficiencies in fxpmath; and potential alternatives going forward

[anurudhp]

Since this will close all those bugs, can you open a bug for classical simulation of fixed point. A brief overview of the current situation where you pass around ints because of deficiencies in fxpmath; and potential alternatives going forward

Done!