In deltack, added check for history group in input cube. If it's there, add a...

In deltack, added check for history group in input cube. If it's there, add a new entry. If not, add a new history group. Added an app test. Fixes #1350.

git-svn-id: http://subversion.wr.usgs.gov/repos/prog/isis3/trunk@5747 41f8697f-d340-4b68-9986-7bafba869bb8