Configuration to make all Hail moves summon Snow or vis versa, to have only one ice weather

[surskitty]

This adds a configuration setting to homogenize Ice weather effects if so desired, making all Hail or Snow summoning moves summon the same weather type.

By default, both Ice weathers are available and moves work the way they do in vanilla games.

Description

I moved battle configurations focusing on weather effects into their own section of include/config/battle.h, then added configuration settings to either: make Hail and Max Hailstorm summon Snow, make Snowscape and Chilly Reception summon Hail, or have both Ice-type weathers. I also adjusted the descriptions of the Hail TM, the Icy Rock, and the move Aurora Veil to reflect which Ice weathers are desired.

Issue(s) that this PR fixes

#6147 is myself requesting this exact feature.

Feature(s) this PR does NOT handle:

I have not added tests as the applicable setting is on the preprocessor level and I don't know how.

Things to note in the release changelog:

• Added a config to homogenize Ice weathers between Hail, Snow, or both.

Discord contact info

wildvenonat

[surskitty]

Apparently if you hack Hail into ScarVio, it summons Snowscape, and Max Hailstorm had its description changed to snow instead of Hail.

I don't think it actually matters whether or not it's canon as it's reasonably clear the game design intention was to replace Hail with Snow, but it is consistent with an in-scope game's stubbed out unlearnable moves. Backporting Chilly Reception is simply for ease of use for Hail-enjoyers.