Make the priority flag description clearer by explicitly referring to "color IDs" instead of "colors"

[RaoulLuque]

When reading the description of byte 3 in the OAM section and more precisely, the priority flag, I was confused whether the sentence
"Priority: 0 = No, 1 = BG and Window colors 1–3 are drawn over this OBJ"
was referring to colors, as in actual colors values (0: White, ...) or whether it was referring to color IDs (which might be mapped by the palette to other color values then their ID might suggest). I suppose it refers to color IDs, which is why I would make that more explicit.

If that is wrong I would suggest changing it to make it clear that color IDs are not meant and instead color values. I was not able to find a conclusive source on this.

Note that the link that is used for the color IDs is the same as used in the palettes section.

[ISSOtm]

Thank you for the contribution! It does indeed refer to colour IDs, your guess was correct!

Would you mind checking the corresponding flag in the BG attributes description (Tile_Maps.md)? I believe it's more or less a copy-paste.

[ISSOtm]

Suggested change

	- **Priority**: `0` = No, `1` = BG and Window [color IDs](./Tile_Data.md) 1–3 are drawn over this OBJ
	- **Priority**: `0` = No, `1` = BG and Window [color IDs](<#Data format>) 1–3 are drawn over this OBJ

We use some custom syntax to more easily link to the appropriate section within other pages.

[RaoulLuque]

Ah, I see, good to know :) I actually copied the link syntax from the one used in the BG palette data description, so should we also update the link there ?