Dice-tower

The largest change to DiceTower in this release is the way we perform our tests. We now have **function mocking** which allows us to validate our tests without accounting for statistical issues. This will mean far less bugs going forward!

We are slowly returning to the previous level of support before the architecture change. The main reason this is slow is because we are taking care to do it in a scalable manner, so that it's easy for others to contribute.
We have renewed support for:
- Fate Die (Improved!)
- Explosions (basic for now)

The backend has been switched from Antler to Yacc/Lex.
This has a few consequences:
- Support of dice types has regressed
- It will be easier to integrate DiceTower into your project
- unicode will no longer be parsed within the tool. Instead use all-caps tokens
- faster, less memory usage (at least theoretically)

Current Support:
- Arithmetic (Improved!)
- Dropping Dice (Improved!)
- xDy notation

Regressed Items:
- Sequences
- Fate Dice
- Explosion & Implosion
- Repetition
- Macros
- Symbol Dice

- Explosion stability :)
- Linting fixes
- Prep for PIP releases
- better cmd flags
- improved testing

+ General coverage increases

Good Support:
- Arithmetic
- Sequences
- Fate Dice
- Standard Explosion & Implosion
- Repetition

Limited Support
- Symbol Dice

Limited support for basic dice and arithmetic.
Pythons support only