Modernise use of find and update_all in database migrations

db/migrate/005_tile_tracepoints.rb

@@ -9,7 +9,7 @@ class TileTracepoints < ActiveRecord::Migration
     if ENV["USE_DB_FUNCTIONS"]
       Tracepoint.update_all("latitude = latitude * 10, longitude = longitude * 10, tile = tile_for_point(latitude * 10, longitude * 10)")
     else
-      Tracepoint.find(:all).each do |tp|
+      Tracepoint.all.each do |tp|
         tp.latitude = tp.latitude * 10
         tp.longitude = tp.longitude * 10
         tp.save!