Follows and relationships (#27)

* Follows -- create and undo, both remote and local
* Statuses -- federate new posts, including media, attachments, CWs and image descriptions.

testrig/federatingdb.go

@@ -0,0 +1,11 @@
+package testrig
+
+import (
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/federation"
+)
+
+// NewTestFederatingDB returns a federating DB with the underlying db
+func NewTestFederatingDB(db db.DB) federation.FederatingDB {
+	return federation.NewFederatingDB(db, NewTestConfig(), NewTestLog())
+}