Open Tree of Life reading is working!  A tree is created in the project automatically after being pulled from the OTL web service.  The tree comes in unrooted, and we need to run a rooting algorithm in the tree before it is displayable.  Saving this before adding the rooting algorithm automatically.
Added rooting ability to api.AddTreeFromString, which is used by OpenTreeOfLife uploads. Also added a datatypeChanged signal emitted from the API, so that datatypes are added after tree uploads, so the UI updates.
Merge branch 'master' of https://github.com/arborworkflows/ProjectManager