Optimize constants

[jasonpaulos]

Summary

PyTeal currently outputs code using the pseudo-ops int, byte, and addr. It's up to the assembler to transform these pseudo-ops into int and byte constant blocks. This process can be optimized to reduce program size if the constant blocks are sorted by decreasing frequency of use, and if the new pushint and pushbytes ops are used for single-use constants.

Scope

• Modify the prototype implementation of this from Add optimization to detect duplicates #41 into a general feature.
• Add an option to compileTeal to enable this feature. By default it should not be enabled to maintain compatibility, at least for now.

Urgency

This has the potential to significantly reduce cost program size for large programs.