Fix character select menu freeze due to smaller then required loop variables

This merge request fixes #304.

In M_CharacterSelectInit inside play-char-select.c there are two variables i and j with the datatype UINT8(255). UINT8 ends up being too small since MAXFOLLOWERS is 1024 and causes the game to lock up in a loop during character menu initialization. To fix this the datatypes for i and j have been made UINT16 so that follower amounts greater then 255 will work.