Install package to speed up test.

Author: AlekSi

Makefile

@@ -1,6 +1,8 @@
 test:
+	go install -race -v
+	go test -i -v
 	go test -race -v .
 
 coverage:
 	go test -coverprofile=coverage.out -v .
-	go tool cover -html=coverage.out
+	go tool cover -html=coverage.out