Fixes #7401 - Add support for bonds

Renames physical_device to attached_to and move the virtual device
form out of BMC.
Extends the form for Bond devices
Allows configuration of bonds in KS template
Parsing of Bond interfaces from facts
on db:migrate i get:

```
The Apipie cache is turned off. Enable it and run apipie:cache rake task to speed up API calls.
==  AddBondAttributesToNicBase: migrating =====================================
rake aborted!
StandardError: An error has occurred, all later migrations canceled:

uninitialized constant Nic::Managed/home/ohad/git/foreman/app/models/nic/bmc.rb:2:in `<module:Nic>'
/home/ohad/git/foreman/app/models/nic/bmc.rb:1:in `<top (required)>'
/home/ohad/git/foreman/app/models/nic/base.rb:84:in `<top (required)>'
/home/ohad/git/foreman/app/models/nic/interface.rb:2:in `<module:Nic>'
/home/ohad/git/foreman/app/models/nic/interface.rb:1:in `<top (required)>'
/home/ohad/git/foreman/app/models/nic/managed.rb:2:in `<module:Nic>'
/home/ohad/git/foreman/app/models/nic/managed.rb:1:in `<top (required)>'
/home/ohad/git/foreman/app/models/nic/bond.rb:2:in `<module:Nic>'
/home/ohad/git/foreman/app/models/nic/bond.rb:1:in `<top (required)>'
/home/ohad/git/foreman/db/migrate/20140910111148_add_bond_attributes_to_nic_base.rb:3:in `up'
/home/ohad/.rvm/gems/ruby-2.0.0-p451/gems/activerecord-3.2.18/lib/active_record/migration.rb:370:in `up
```