Use as workers as CPUs on Debian and derivative

As recommended
Merge pull request #7 from sathieu/for_upstream

Use as workers as CPUs on Debian and derivative
Automatic README conversion from rdoc to md
Enabling Travis integration
Added Travis Status icon
Fixed service autorestart spec test
Fixing Travis compatibility matrix
Modified data_dir, set all distros to default value to
"/usr/share/puppet-dashboard/" as Deabian and RedHat based distros use
the same path.
Merge pull request #8 from brdude/master

Fixed data_dir for RedHat based distros.
Merge pull request #2 from example42/master

Upstream pull