Feature/add support for filesystem labels

[unki]

e.g.

    logical_volumes:
      opt:
        size: 20G
        use_fs_label: true

will then lead to

• formating the filesystem by mkfs.ext4 -L opt /dev/vg-xyz/opt. the most mkfs's implement the -L label-parameter. So it shouldn't be necessary to make it configurable.
• /etc/fstab entry LABEL=opt /opt ext4 defaults 0 0

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[puppet-community-rangefinder]

lvm::logical_volume is a type

Breaking changes to this file WILL impact these 1 modules (exact match):

• glorpen-g_server

Breaking changes to this file MAY impact these 1 modules (near match):

• example42-psick

lvm::volume_group is a type

Breaking changes to this file MAY impact these 1 modules (near match):

• example42-psick

This module is declared in 11 of 576 indexed public Puppetfiles.

---

These results were generated with Rangefinder, a tool that helps predict the downstream impact of breaking changes to elements used in Puppet modules. You can run this on the command line to get a full report.

Exact matches are those that we can positively identify via namespace and the declaring modules' metadata. Non-namespaced items, such as Puppet 3.x functions, will always be reported as near matches only.

[unki]

failing tests are afaics not related to my changes.
possibly gets fixed by #260