Move bootstrap tasks into the Makefile

This is more consistent with how we run all other tasks. Note that
the virtual env setup is not generally applicable, and developers
of this repo should follow the guidance in the README.

Makefile

@@ -22,6 +22,11 @@ VIRTUALENV_ROOT := $(shell [ -z $$VIRTUAL_ENV ] && echo $$(pwd)/venv || echo $$V
 
 ## DEVELOPMENT
 
+.PHONY: bootstrap
+bootstrap: generate-version-file
+	pip3 install -r requirements_for_test.txt
+	npm install && npm run build
+
 .PHONY: run-flask
 run-flask:
 	. environment.sh && flask run -p 6012