Merge remote-tracking branch 'origin/uvcdat-283-load-vt-multiple-chained-computed-vars' into uvcdat-master

* origin/uvcdat-283-load-vt-multiple-chained-computed-vars:
  Fix bug when loading vt containing multiple chained computed vars
Merge remote-tracking branch 'origin/uvcdat-282-time-bounds-on-derived-vars' into uvcdat-master

* origin/uvcdat-282-time-bounds-on-derived-vars:
  Make time bounds operations work with compute variables
Merge remote-tracking branch 'origin/uvcdat-284-add-time-bounds-test' into uvcdat-master

* origin/uvcdat-284-add-time-bounds-test:
  Adds config option to run a single specified test
  Adds test and support methods for derived time bounds
  Initial work on adding time bounds with computed variables test
Merge remote-tracking branch 'origin/uvcdat-285-load-saved-vcs-isofill-bug' into uvcdat-master

* origin/uvcdat-285-load-saved-vcs-isofill-bug:
  Gaurd for None during plot type-checking
Use new signals in vcs animation object.
Update Animation widget when selected cell changes.
Disable dimesion selector after creating animation
Merge branch 'uvcdat-291-vcs-animation-gui' into uvcdat-next