Incorrect comments in learning RNG Files

Comments in learningObjectMapMod.rng and learningGroupMapMod.rng refer to
the wrong URNs.  Fix is to correct the URNs referenced in the comments to
reflect the URN for the file itself. This is a nonmaterial change that
cannot affect functioning of the grammar files in any DITA-defined way.

Cheers,

E.
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Eliot Kimber, Owner
Contrext, LLC
http://contrext.com