New URI implementation with relative URIs support

* New URI implementation with different options and support for relative
* Code and programs not immediately part of updater were moved to
  separate repositories. This move consists of supervisor, localrepo and
* Thanks to new URI implementation the memory consumption was
  drastically reduced.
* All files are removed early in install phase instead of on late
  cleanup. This solves problem with postinstall and postrm scripts
  accessing and detecting files that were marked to be removed.
* Fixed fatal fail when package was limited on non-existent repository.
  This is now just warning and other existing allowed repository is used
* Introduced new --reinstall-all option for pkgupdate which allows to
  force reinstall of all packages.
* All binaries now use argp as argument parser instead of proprietary
  implementation. On non-glibc systems you can use argp-standalone.