adding go.mod file

go.mod

@@ -0,0 +1,15 @@
+module github.com/gobuffalo/tags
+
+require (
+	github.com/fatih/structs v1.0.0
+	github.com/gobuffalo/envy v1.6.3
+	github.com/gobuffalo/uuid v1.2.0
+	github.com/gobuffalo/validate v1.0.0
+	github.com/joho/godotenv v1.2.0
+	github.com/markbates/going v0.0.0-20170113214412-0576708c56ce
+	github.com/markbates/inflect v0.0.0-20180514174915-dd7de90c06bc
+	github.com/markbates/validate v1.0.0
+	github.com/pkg/errors v0.8.0
+	github.com/satori/go.uuid v1.2.0
+	github.com/serenize/snaker v0.0.0-20171204205717-a683aaf2d516
+)