Fixed typo in /region help message, and added /region remove (Fixed Line Endings)

TShock version number: 4.0.0.0923
How to reproduce: Execute server command /region

Before: Avialable
After: Available

/region remove was not listed in the help dialog, so I added that.

This time, I've used the lf line endings and excluded .pdb, .exe, and .dll files as binaries.

Some thanks to Ijwu