Set retry_max_delay to 5 seconds so that reconnects don't slow down exponentially

libraries/redis-wrapper/index.coffee

@@ -2,6 +2,9 @@ _ = require("underscore")
 
 module.exports = RedisSharelatex =
 	createClient: (opts = {port: 6379, host: "localhost"})->
+		if !opts.retry_max_delay?
+			opts.retry_max_delay = 5000 # ms
+		
 		if opts.password?
 			opts.auth_pass = opts.password
 			delete opts.password