Explicitly use python3 on ReadTheDocs.

tannewt · tannewt · commit eae46bc041cb · 2017-12-01T16:44:58.000-08:00
Without this, circuitpython-travis-build-tools cannot be installed
by it. (It installs it because its listed in requirements.txt)
diff --git a/{{ cookiecutter.library_name }}/readthedocs.yml b/{{ cookiecutter.library_name }}/readthedocs.yml
@@ -1,2 +1,3 @@
+python:
+    version: 3
 requirements_file: requirements.txt
-

Original file line number	Diff line number	Diff line change
`@@ -1,2 +1,3 @@`
	`1`	`+python:`
	`2`	`+ version: 3`
`1`	`3`	`requirements_file: requirements.txt`
`2`		`-`