Note file security mode recorded format

Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Add a README

This duplicates the information in the schema header, with some slight
reformatting.

Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Document <id> role in light of other id mechanisms

Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Mark "version" attribute on "creator" element for removal

This attribute appears to be unused in all current tooling, and only
provides redundant information.

This addresses Issue 2:
<https://github.com/dfxml-working-group/dfxml_schema/issues/2>

Acked-by: Mark Matienzo <mark.matienzo@gmail.com>
Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Clarify dual purposes of library element

Reported-by: Cliona Curley <cliona.curley@ucd.ie>
Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Deprecate hashdigest/@base attribute

After initial reporting, my conclusion is that this attribute is
vestigial.  If somebody has a need to write hashes in a base other than
16, we can restore this attribute, but so far I have not come across
such a need, inspecting the source of the DFXML C++ library, PhotoRec,
Hashdeep, and Fiwalk.

Reported-by: Cliona Curley <cliona.curley@ucd.ie>
Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Clarify specification of parent_object

Reported-by: Cliona Curley <cliona.curley@ucd.ie>
Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Add error reporting to volumes

This addresses Issue 20:
<https://github.com/dfxml-working-group/dfxml_schema/issues/20>

Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Allow metadata to have multiple children

The defaults of the metadata child specifications only allowed 0 or 1
elements.  This was accidental.

This commit resolves Issue 17:
<https://github.com/dfxml-working-group/dfxml_schema/issues/17>

Reported-by: Cliona Curley <cliona.curley@ucd.ie>
Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Relax UID/GID type definition for NTFS

One DFXML generator outputs NTFS SIDs for the uid element:
<https://github.com/Sebastienbr/DFXML-EnCase/blob/master/DFXML.EnScript#L743>

For NTFS, it would be appropriate, and infinitely more useful, to allow
<uid> to be a string.  For other file systems, the usual numeric
constraint should still be noted.

Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Allow other namespaces under metadata element

processContents is being left as "lax" to avoid requiring people to
write other schemas for validating with custom namespace elements.
Requiring "strict" validation of other namespaces ends up requiring a
lattice structure of schema files importing one another.

Reported-by: Cliona Curley <cliona.curley@ucd.ie>
Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>
Merge pull request #22 from ajnelson/for_v1.1.1

For v1.1.1
Declare v1.1.1

Signed-off-by: Alex Nelson <a.nelson@prometheuscomputing.com>