Minor fixes not worth their own individual PRs.

[AliceLR]

Fixes for minor bugs introduced by new features that individually weren't worth their own PR.

• Fixed system time counters not updating in the variable debugger on refresh.
• Fixed MegaZeux's built-in mixer resample mode variable name.
• Bumped DJGPP's default module mixing mode back up to linear (from nearest).
• Fixed 1.x centered message column values being imported incorrectly.
• Fixed about.c license file list not getting fully populated in DOS with LFNs disabled.
• Fixed licenses not displaying in the 3DS port when using executable paths other than /3ds/megazeux.
• Fixed "3rd Party" appearing before "License" in the license list on platforms without sorted dirent.