Propagate bug fix of wsElNodeID bug from temp merge branch to master.

wsElNodeID was holding local rather than global IDs after a recent commit to
master. Restore original behavior of holding gids.
Remove ifdef SG_MP guards now that code is working.
Make some mods to new ATO code.

1. Mod ATO/CMakeLists.txt to handle DOTk dependency.

2. Restore original wsElNodeID-based gid lookup. A bug in a recent commit had
temporarily made wsElNodeID return lids rather than gids; I fixed that bug
(previous commit) and have now restored the ATO code snippets that use that
index lookup to their original forms. Sorry ATO team about the confusion!

All tests are in their nominal form; in particular, the 6 ATO tests pass.