Enhancement: Move reporting metrics to postgres (#606)

db/migrate/20200310062527_create_events.rb

@@ -0,0 +1,14 @@
+class CreateEvents < ActiveRecord::Migration[6.0]
+  def change
+    create_table :events do |t|
+      t.string :name
+      t.float :value
+      t.integer :account_id
+      t.integer :inbox_id
+      t.integer :user_id
+      t.integer :conversation_id
+
+      t.timestamps
+    end
+  end
+end