Improve base power modifiers

[DaWoblefet]

Implements most of the base power issues in #443; I didn't want to do everything at once so it'd be easier to code review. Notably, I did not implement the Speed-based modifier chaining yet; I'll need to think about that some more and want to tackle it in a separate PR once I take care of the low-hanging fruit.

Moves with custom BP:

• Steel Roller and Poltergeist now fail earlier before even entering BP calculation
• Payback, Acrobatics, Weather Ball now no longer use hardcoded damage values
• Pursuit was changed to be a move with variable base power
• Smelling Salts and Triple Kick were added as moves with variable base power
• Gyro Ball's formula was corrected

Base Power modifiers:

• BP modifiers are now grouped by effect type (move, ability, etc.) then by modifier
• Zamazenta with Rusted Shield doesn't increase Knock Off
• Expanding Force, Rising Voltage, and Misty Explosion changed to base power modifiers
• Technician's mechanics were corrected (the past theory about temporary chaining is very wrong)
• Aura mechanics were corrected (they only apply once)
• Punk Rock (offensive) changed to a base power modifier

Misc:

• Terrain Pulse and Nature Power now list their typing and base power in desc

[DaWoblefet]

Well the linter is complaining but idk what I did wrong here; I changed max-len in eslint from 100 -> 120 to match Showdown's server line length limit but apparently it didn't like that :(

[DaWoblefet]

Another bump for review @KrisXV - I wanted to get the entirety of #443 done over the summer. I'll merge myself if you're still busy, since these are objective bugfixes.

[KrisXV]

thx