Have CLM listen to the driver for number of threads rather than OMP_NUM_THREADS

**Erik Kluzek < erik > - 2017-02-10 18:10:02 -0700**
**Bugzilla Id:** [2421](http://bugz.cgd.ucar.edu/show_bug.cgi?id=2421)
**Bugzilla CC:** dlawren, mvertens, rfisher,

This is CLM's part of Issue 864 for cime, where the components don't listen to what the driver sets the number of threads for them -- but use the env variable OMP_NUM_THREADS

https://github.com/ESMCI/cime/issues/864

This can be a problem if another component is threaded, and you don't want CLM to be. It'll end up being threaded anyway.