Migrate check_host util to Pkg::Util::Net

One by one, we're going to remove *all* utils from 00_utils.rake and move them
into classes. This continues that work with 'check_host'.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Migrate 'remote_ssh_cmd' to Pkg::Util::Net

One by one I want to migrate these utilities over to the libraries while I have
a quiet moment or two. Here's another one.
(maint) Move socket require to top of net_spec
(maint) Change expect to should in net_spec
(maint) Remove unnecessary stubs in net_spec
Merge pull request #9 from haus/maint/master/migrate_utils

Update specs based on comments I left
Remove hostname method no longer used

The hostname method was migrated to Pkg::Util::Net. This commit removes it from
00_utils.rake.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Merge pull request #270 from MosesMendoza/maint/master/migrate_utils

Migrate check_host and remote_ssh_cmd to library