common: Add prebuilt extract tool

I created this tool to allow extracting various file types with ease.
The following file types are supported..

  * .tar.bz2
  * .tar.gz
  * .bz2
  * .gz
  * .rar
  * .tar
  * .tbz2
  * .tgz
  * .zip
  * .Z

Simply open a terminal and type 'extract FILENAME' to extract any of
the file types above.

Also add 'unrar' utility to build

Change-Id: I0445d690db4835b9925f51c4d73499d6761fdd0b
Signed-off-by: Rob Beane <robbeane@gmail.com>