Refactor qtree spec tests

The type spec tests should not put any dependencies on providers so
create dummy providers and use them instead of the real ones.

As a sideeffect we have to require puppet/util/network_device at a
puppet type level (instead of provider level) because the libraries
would not get loaded otherwise and `apply_to_device` (used at a type
level) seems to depend on these libraries.
Simplify ensure property of qtree type

The block passed to the ensurable method is basically the default
behaviour as defined in puppet/property/ensure.rb#self.defaultvalues

Ommit the block and use the default
Modify qtree to autorequire volume

A qtree is always created on a specific volume. As a result this volume
has to be present before the qtree can be created, so a qtree should
autorequire its volume.

Add the described autorequire.
(#32) Fixed an issue when running rspec tests for netapp_qtree. Also fixed the issue with 'should support hyphens' test.
Merge branch 'master' of https://github.com/fatmcgav/fatmcgav-netapp