apt-cacher-ng-3.1-bp150.2.4

- Use more of cmake macros
- Use pkgconfig style dependencies

- Version bump to 3.1
  * Hide credentials in acngtool in some corner cases
  * Dropped references to distkill.pl script which was superseeded by acngtool
  * Made default PassThroughPattern setting stricter
  * Mirror database update
  * Avoid expiration failure when some index files are missing
- Fix logrotate file installation

- Trim description. Use regular %setup call for all unpacking.

- Initial commit