Feature/terminology

[dconlan]

Hi Orion,

I've created this feature based on your old selectize branch. It adds a number of ways to use alternative terminology providers to do autocomplete on disorders, phenotypes and genes. I've written a bit of documentation on it in the terminology.md file.

I've not tested the CTSS terminology as I haven't ever setup a phenotips server for it to use.

I'm not sure the best way to deal with things like the bioportal api key or a fhir terminology server that needs authentication. I do have some code thats part of my redcap plugin that uses redcap as a proxy and it hides the keys and does the authentication. But I didn't include it in this pull request as its tightly coupled to the redcap plugin and so is not relevant to others.

David Conlan