make: silence pip command

sbadia · sbadia · commit 479637420caf · 2017-12-27T11:40:58.000+01:00
diff --git a/Makefile b/Makefile
@@ -38,7 +38,7 @@ sourcevenv:
 	fi
 
 install: venv sourcevenv
-	pip install -e .
+	@pip install -e .
 
 build: sourcevenv deps
 	gitoyen build
