Remove Q_atoi - use SDL_atoi instead
Remove Q_atof - use SDL_atof instead
Remove [custom] vsnprintf - use SDL_vsnprintf instead
Remove [custom] snprintf - use SDL_snprintf instead
Remove [custom] snprintf - use SDL_snprintf instead (part 2)

I missed a file the first time.  :p
Remove [custom] strcasecmp - use SDL_strcasecmp instead
Remove [custom] strncasecmp - use SDL_strncasecmp instead
Remove [custom] strlcpy - use SDL_strlcpy instead
Remove [custom] strlcat - use SDL_strlcat instead
Remove unused custom strnstr function
Remove unused IS_SLASH macro
Remove [custom] strchrrev - use SDL_strrchr instead
Remove unused Q_ftos function
Remove Q_strlwr - use SDL_strlwr instead
Replace snprintf with SDL_snprintf (part 2)

Oops, I missed these in the first commit switching over to SDL_snprintf.
Replace snprintf with SDL_snprintf (part 3)

Oops, these keep sneaking up on me...
Merge branch 'creamquake3' of https://github.com/qwcream/ezquake-source into creamquake3
Replace all calls to atoi with calls to SDL_atoi

For consistency.
Replace all calls to atof with calls to SDL_atof

For consistency.
Merge branch 'creamquake3' of https://github.com/qwcream/ezquake-source into qwcream3

Conflicts:
	vid_sdl2.c