buildtorrent (0.9.1-4)

This merge request closes an ITA bug: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1119040.

Mentors link: https://mentors.debian.net/package/buildtorrent/.

Changes:

 * Adoption of package. (Closes: #1119040)
 * 'debian/copyright':
   - Add myself to 'Files: debian/*' section.
 * 'debian/control':
   - Bump Standards-Version to 4.6.3.
   - Remove Priority field from debian/control.

Please let me know if there is any feedback that I can address.