More human-friendly names for some constants

[ISSOtm]

Taking inspiration from pokecrystal's constants, for example. This would allow them to use hardware.inc, as well. (cc @Rangi42)

[rawr51919]

While not impossible, it required a good chunk of constant names to be rewritten to make pokecrystal work under hardware.inc as it exists now

[rawr51919]

Taking inspiration from pokecrystal's constants, for example. This would allow them to use hardware.inc, as well. (cc Rangi42)

PR #32 shows what a hardware.inc with those constants would look like, to me it seems kinda cluttery since a lot of the same constants are more concise as they are. Yet it's there in case others want to weigh in on this.