Remove references to requirements

MANIFEST.in

@@ -1,4 +1,4 @@
-include *.md LICENSE requirements*.txt config-sample.json
+include *.md LICENSE config-sample.json
 exclude config.json TODO.md
 
 graft src

Makefile

@@ -73,17 +73,3 @@ dist: clean docs
 	$(PYTHON) setup.py sdist
 	$(PYTHON) setup.py bdist_wheel
 	ls -l dist
-
-update-reqs: requirements-dev.txt
-	@$(GREP) --invert-match --no-filename '^#' requirements*.txt | \
-		$(SED) 's|==.*$$||g' | \
-		xargs ./.venv/bin/python -m pip install --upgrade; \
-		for reqfile in requirements*.txt; do \
-			echo "Updating $${reqfile}..."; \
-			./.venv/bin/python -c 'print("\n{:#^80}".format("  Updated reqs below  "))' >> "$${reqfile}"; \
-			for lib in $$(./.venv/bin/pip freeze --all --isolated --quiet | $(GREP) '=='); do \
-				if $(GREP) "^$${lib%%=*}" "$${reqfile}" >/dev/null; then \
-					echo "$${lib}" >> "$${reqfile}"; \
-				fi; \
-			done; \
-		done;