CMS-4529 Content Permissions - Merge inherited and non-inherited permission lists

- rearranged RichComboBox's getter names
- remove the "Inherit permissions" checkbox and line separator
- remove the inherit permission list at the bottom (AccessControlListView)
- add both Content.getPermissions  and Content.getInheritedPermissions to the combobox
- entries that come from the inherited list, will show the unset state in grey (same as currently disabled items)
- entries that are not from the inherited list, will show the unset state in white
- all the rows can be removed (including inherited entries)
- when an entry is modified, the text in the AccessSelector ("Can Read") should become blue
- add a link at the bottom right, labelled "Restore" that resets to parent effective permissions (same as on new)
- only the modified data should be saved, this will be handled on a separate task, for now just take the whole list from the combobox