Manage DEIMS api versions

New API are coming. We must be able to adapt our logics to changes. We can test on pre-production site with different url. Proposal (partially done):

create global but adjustable package setting with base deims url (configurable in one's system variable) - done
use package onLoad function to possibly change the base url variable reading from system. - done
use a function to read from baseurl/api the deims version - done
set a global (changeable) package setting to the read version (it's a string). - TODO
put JQ queries in a variable (list) containing slots for API versions (e.g. jq_queries$'1.0' will be a list).
adapt each function that contains a jq query to the new pattern: move the jq code into the JQ_queries variable. - STARTED for api version "1.0"
add jq queries for version "1.1" and test the package against the pre-prod new version of deims - TODO

ropensci / ReLTER