Use bosh common to shell out

Change-Id: I09f132a3473d03d26d19678441e3c8e876af33cf
Use File.blockdev? instead of File.stat

Change-Id: I72b013e20e077ebe1042da0ca5f5e2cce0567a4e
Use Sigar to check if partition is mounted

Change-Id: I5066e4c3d471784a43a1273eb5e65ea1c23d8efc
Add test for partition path

Change-Id: I63edfc3273a3f0e93e433801eb719d0ecb3412c3
rhel => redhat

Change-Id: I1bdcd0fec956ec46ef2a3775a3b488796726e833
Verify mac address is valid

Change-Id: I3b57f6f0605d3782899e4ad2fe318638fb9fcad4