Fix tree and study properties hack

[snacktavish]

This mixes together JSON and non JSON properties in a confusing way. https://github.com/OpenTreeOfLife/otindex/blob/options/otindex/util.py#L14

Potentially related to:
#31

#29

[snacktavish]

@kcranston Should we update the tree and studies properties that are returned and API docs to only include these properties? #16
Will updating the properties that are searchable require incrementing the api?

[snacktavish]

#18 I was confused by the "tree properties not in nexsons" bit of this sissue. Original label is in nexsons, right?

[snacktavish]

@kcranston This was fixed in 259f670, right?