add README for contributing

README.md

@@ -0,0 +1,46 @@
+## Contributing a Model
+
+1. Put the model's `.ttl` file in the `models/` directory
+2. Create a `.md` file *with the same base name as the `.ttl` file* in the `examples/` directory:
+    - This `.md` file should have at least the following 3 *empty* sections, in this order:
+    - `## Downloads`
+    - `## Queries`
+    - `## Model Components`
+3. Add this `.md` file to the `_toc.yml` file under the appropriate section (Building or System)
+4. If you want to add queries to the model, add them in `queries.toml`. The section name should have the same base name as the `.ttl` and `.md` file.
+
+
+### Example
+
+For a model called `mybuilding.ttl`, the following files would be created:
+- `models/mybuilding.ttl`
+- `examples/mybuilding.md`
+
+The `examples/mybuilding.md` file would look like this:
+
+```
+# My Example Building
+
+<description of the building>
+
+## Downloads
+
+## Queries
+
+## Model Components
+```
+
+The `queries.toml` file might look like this:
+
+```toml
+[[mybuilding]]
+description="Zone/room temperature sensors"
+query="""
+SELECT ?location ?sensor WHERE {
+    ?sensor rdf:type/rdfs:subClassOf* s223:Sensor .
+    ?sensor s223:observes ?property .
+    ?property qudt:hasQuantityKind quantitykind:Temperature .
+    ?sensor s223:hasObservationLocation ?location
+}
+"""
+```