Move all migrations to separate file

Also fixed some inconsistent uses of snake case.

daemon.go

@@ -1,50 +0,0 @@
-package main
-
-import "time"
-
-// https://bbengfort.github.io/snippets/2016/06/26/background-work-goroutines-timer.html THANKS
-
-type inviteDaemon struct {
-	Stopped         bool
-	ShutdownChannel chan string
-	Interval        time.Duration
-	period          time.Duration
-	app             *appContext
-}
-
-func newInviteDaemon(interval time.Duration, app *appContext) *inviteDaemon {
-	return &inviteDaemon{
-		Stopped:         false,
-		ShutdownChannel: make(chan string),
-		Interval:        interval,
-		period:          interval,
-		app:             app,
-	}
-}
-
-func (rt *inviteDaemon) run() {
-	rt.app.info.Println("Invite daemon started")
-	for {
-		select {
-		case <-rt.ShutdownChannel:
-			rt.ShutdownChannel <- "Down"
-			return
-		case <-time.After(rt.period):
-			break
-		}
-		started := time.Now()
-		rt.app.storage.loadInvites()
-		rt.app.debug.Println("Daemon: Checking invites")
-		rt.app.checkInvites()
-		finished := time.Now()
-		duration := finished.Sub(started)
-		rt.period = rt.Interval - duration
-	}
-}
-
-func (rt *inviteDaemon) shutdown() {
-	rt.Stopped = true
-	rt.ShutdownChannel <- "Down"
-	<-rt.ShutdownChannel
-	close(rt.ShutdownChannel)
-}