858877 Allow selection of all listem items when applying packages to a system group

Added select_all and deselect_all button for system group when all erratas
wanted to be checked.
Using OPTIONS method on Pulp API to find out it's running

We check the content_length, that should be non_zero, when everything
is ok.
abstract model - parse attributes properly on create
foreman model - support for different resource name in foreman
hw models - model and api
hw models - cli for listing
hw models - fix for api binding comments
hw models - cli for info
hw models - cli for creation
hw models - cli for deletion
hw models - cli for update
hw models - system tests
hw models - cli refactoring
hw models - ui pages
kt form builder - support for label help icon
Merge pull request #1421 from tstrachota/models

API & CLI for HW models
Merge pull request #1495 from iNecas/pulp-ping-fix

Using OPTIONS method on Pulp API to find out it's running
Added rubygem-excon to comps for F16 and F17

It is required bysmart proxy
Merge pull request #1505 from mbacovsky/rubygem_excon_in_fedora_comps

Added rubygem-excon to comps for F16 and F17
refactoring of default system registration permission and user own role code in User model