Sentry Buster model override

This mod makes Sentry Busters use the regular demobot model instead of the version with the modified top half.

Useful when trying to figure out why stuff is screwed up, because the demobot model is less broken than the Sentry Buster model.

Note about sv_pure

This mod will not work on sv_pure servers (including Valve servers). It will only work on servers that don't enforce sv_pure on the files that are modified.