Added missing data elements to BD profiles.

Added missing data elements from PS3.11 Table H.3-2 to the various Blu-ray
Disc (BD) media storage application profiles. Basically, the requirements for
PATIENT, IMAGE and SPECTROSCOPY directory records are identical to those for
the DVD profiles. Only the reference in Section M.3.3.1 was missed.
Added check for Shared Functional Groups Sequence.

Certain key attributes like Pixel Spacing (0028,0030) can also be nested
within a functional group sequence of the Shared Functional Groups Sequence
(5200,9229). Therefore, these attributes also have to be checked on this level
and not only in the main dataset.