Betsy McPhail authored Oct 04, 2018 and Brad King committed Oct 10, 2018

Teach CTest to submit Done.xml. Submission of this file indicates to
CDash that a build is complete and no more files will be uploaded. It
contains the build id returned by CDash and the current time.

This file is submitted last for a given build when using the
`ctest_submit()` command.

If submitting by PARTS, use `ctest_submit(PARTS Done)`.