Install python-crypto package FIXES #6

On squeeze this package is not installed by default.
bump version to 2.0.1
add support for Facter < 1.6.1 FIXES #7

On debian squeeze, the facter default version is 1.5.7 or the
$::osfamily fact was introduced with facter 1.6.
Update changelog for 2.0.1 release
Merge branch 'v2.0.1'