Replaced Subito/Linux-libre with Shahor.

Shahor is the new flagship distribution of roar-ng II. It is built from Debian
Wheezy packages, combined with packages built using roar-ng II. Currently, a
Raspbian-based ARMv6 port is under heavy development.

Changes introduced in this commit:
  - A new feature of automated package license installation was added to
    buildpkg. This feature makes it easier to find the license of packages with
    a common license (e.g GPLv2).
  - /etc/hpmrc was removed, since this file contains only constants. Because
    these constants are also used by roar-ng II, they were moved to the common
    functions file.
  - hpm was enhanced with the ability to remove packages that ship as part of
    the of the built distribution. The code which registers an installed package
    became part of the common functions file and can be used in order to
    register packages in a root file system located at a given prefix. It gets
    called by roar-ng II when the root file system is built, for every package.
  - Package updates:
    - LFTP 4.4.2 -> 4.4.3
    - aria2 1.16.1 -> 1.16.3
    - Linux 3.2.37 -> 3.2.38