Merge pull request #1756 from obi-ontology/new_imports_docs

 Adds documentation on how to import from a new ontology

README.md

@@ -29,6 +29,23 @@ Our ontology terms come in three groups. Depending on what type of term you want
 
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+### Importing from a New Ontology
+
+If you wish to import terms from an ontology for which OBI does not currently have an OntoFox import file ([`src/ontology/OntoFox_inputs/`](src/ontology/OntoFox_inputs/)), follow these steps:
+
+1. Write the import file for the new ontology (see existing import files for reference).
+2. Update [`catalog-v001.xml`](src/ontology/catalog-v001.xml) to list the new import file like it lists the existing import files.
+3. Add an import statement to [`obi-edit.owl`](src/ontology/obi-edit.owl).
+4. Create a blank file for the output module in [`src/ontology/OntoFox_outputs/`](src/ontology/OntoFox_outputs), e.g., to make phony output for foo.owl imports:
+```
+touch src/ontology/OntoFox_outputs/foo_imports.owl
+```
+5. Build the module & obi.owl.
+```
+make imports
+make obi.owl
+```
+
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