Create adapter for OpenIMIS

See https://release.openimis.org/api/api_fhir_r4/docs/swagger/#/ for an OpenAPI spec and https://openimis.atlassian.net/wiki/spaces/OP/pages/3220930578/Release+openIMIS for a howto. The actual information on what is integrated is here: https://docs.google.com/presentation/d/1IZh5FQIqgmVkk7KU0ui8ETVaFawfsT-DFO8Zql6G-mU/edit#slide=id.g115e6b97f30_1_0 - feel free to ask me questions!