ECDR-48 minor changes for fortify issues marked as "low"

@mrmateo  - Check out the Fortify issues if you need more details.

I figured there were enough changes that I would create  a PR for them.  Also I forgot to merge in your latest, so I had to do a manual merge of the AbstractCDRSource, so just double check that I didn't accidentally screw something up.

Finally - check out the update I did for skip.  Fortify flagged this, so then I looked into it, and found out that the inputStream.skip method is pretty bad.

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