avoid use of /dev/disk/by-id in VirtualBox

/dev/disk/by-id is not stable in VirtualBox so we don't want to rely on
it.
Merge pull request #203 from aspiers/virtualbox-disk-by-id

avoid use of /dev/disk/by-id in VirtualBox
Read /sys/block/<device>/queue/rotational, so we can check for SSD disks
(SSD device has rotational == 0)
Merge pull request #211 from jsuchome/queue_rotational_info

Read /sys/block/<device>/queue/rotational, so we can check for SSD disks
add travis testing support
Merge pull request #212 from dirkmueller/master

add travis testing support
Add optional crowbar-applied boolean attribute to schema

Set it to false by default in the json and update proposal schema
version to 3.
Merge branch 'release/roxy/master' into merge-roxy
Merge pull request #213 from bkutil/add_applied_attribute

Add applied attribute
Merge pull request #214 from vuntz/merge-roxy

Merge roxy branch into master
Simplified/fixed UEFI config (bnc#865871)

I have simplified the UEFI configuration in order to get the
installation on UEFI hardware running. I extracted the UEFI informations
into an ohai plugin. This fixes
https://bugzilla.novell.com/show_bug.cgi?id=865871
Merge pull request #216 from tboerger/feature/uefi-fix

Simplified/fixed UEFI config (bnc#865871)