Adapt general logic to use underscores for JSON scope names

The inspector, renderer and system_description classes were adapted to
use underscores a separators for JSON scope names.
The usage of the the command line scope names wasn't changed though,
they still use dashes as separator.
Adapt unmanaged-files logic to use "_" for JSON

The unmanaged-files logic was adapted to use underscores as separators
for JSON scope names.
The usage of the the command line scope names wasn't changed though,
they still use dashes as separator.
Adapt config-files logic to use "_" for JSON

The config-files logic was adapted to use underscores as separators for
JSON scope names.
The usage of the the command line scope names wasn't changed though,
they still use dashes as separator.
Adapt changed-managed-files logic to use "_" for JSON

The changed-managed-files logic was adapted to use underscores as
separators for JSON scope names.
The usage of the the command line scope names wasn't changed though,
they still use dashes as separator.
Replace repeated Inspector.all_scopes call by attribute
Add CLI methods to convert scope names

Since scope names are now stored with an underscore internally we need
to convert them in both directions.
Both methods accept a string or an array and return an array because
the common use case is to have a list of scopes.
Merge pull request #58 from SUSE/make_json_attributes_spelling_consistent

Make json attributes spelling consistent
Separate pattern release from version
Always only store name, version and architecture in the os scope
Incorporate suggestions
Merge pull request #66 from SUSE/review_140811_only_store_name_arch_and_version_in_os_scope

Always only store name, version and architecture in the os scope
Data format cleanup: Change error reporting for changed_managed_files

Introduce a "status" attribute for files in changed_managed_files scope.
Its value is either "changed" (in which case the changes are described
in the "changes" attribute) or "error" (in which case the error
encountered when detecting changes is described in the "error_message"
attribute).

This replaces previous "error" attribute. The advantage is that readers
don't have to rely on its presence/absence to determine file state.
Merge pull request #65 from SUSE/data-format-cleanup-patterns

Separate pattern release from version
Merge branch 'data-cleanup-changed-managed-files-status'

Conflicts:
	plugins/show/changed_managed_files_renderer.rb
Data format cleanup: Introduce "status" for config_files

Introduce a "status" attribute for files in the config_files scope. This
mimics a similar attribute in the changed_managed_files scope. For now,
the value is always "changed" as we don't detect errors in
ConfigFilesInspector in the same way as in ChangedManagedFilesInspector.
Merge pull request #72 from SUSE/data-cleanup-config-files-status

Data format cleanup: Introduce "status" for config_files
Also store release of packages besides the version
Merge branch 'review_140812_store_package_release'
Data model docs: Add toplevel header

This was added automatically when this document was in the wiki, but it
needs to be inserted manually now that it is in the main Git repo.
Data model docs: Unify header capitalization