Add DurationMsg to CheckMsg union
Add DurationMsg to CheckMsg union

As the CheckMsg union is passed around to the various
pack/upack functions, and a DurationMsg is valid to be
passed around, include it in the union just in case
the DurationMsg is or becomes larger than the other
members.

Patch provided by Michael Piszczek

git-svn-id: d023f1085a36f7a677188d00334e37d38ffecf51@1153 64e312b2-a51f-0410-8e61-82d0ca0eb02a

krichter722/check,krichter722/check,brarcher/check,9fcc/check,brarcher/check,krichter722/check,brarcher/check,9fcc/check,brarcher/check,libcheck/check,9fcc/check,9fcc/check,libcheck/check,libcheck/check,krichter722/check,libcheck/check,9fcc/check,libcheck/check,brarcher/check,krichter722/check