Skip over bad commits, rather than bombing out

I've been getting lots of "Unexepected Commit message" errors when using this script. Eg:

    Unexpected Commit format!
    46424c5d475687c198436a3dcce6d2902a7d12ca
    Merge: daac25d 9008585
    Author: barrywe7 <barry@we7.com>
    Date:   Fri Dec 20 02:45:14 2013 -0800

        Merge pull request #2748 from robertoaltieri/MergeDevelop
    
        Merge develop

I've not worked out the cause of the failure to parse, however, They are all merges and I don't care about any of these commits since they don't form part of the changelog.

I've adapted the script to simply skip over these commits.  The error messages are still logged, but the script outputs the release notes successfully.