make: separate phony for each target

Part of #198

Author: DifferentialOrange

Makefile

@@ -1,15 +1,29 @@
-.PHONY: install test docs
+.PHONY: install
 install:
 	pip3 install --editable .
+
+
+.PHONY: test
 test:
 	python3 setup.py test
+
+.PHONY: testdata
 testdata:
 	cd ./test/data/; ./generate.sh
+
+.PHONY: coverage
 coverage:
 	python3 -m coverage run -p --source=. setup.py test
+
+.PHONY: cov-html
 cov-html:
 	python3 -m coverage html -i
+
+.PHONY: cov-report
 cov-report:
 	python3 -m coverage report
+
+
+.PHONY: docs
 docs:
 	python3 setup.py build_sphinx