enable Ruby 2.2 compat checks in Rubocop, correct multi/handler compat

.rubocop.yml

@@ -8,6 +8,9 @@
 
 # inherit_from: .rubocop_todo.yml
 
+AllCops:
+  TargetRubyVersion: 2.2
+
 Metrics/ClassLength:
   Description: 'Most Metasploit modules are quite large. This is ok.'
   Enabled: true

modules/exploits/multi/handler.rb

@@ -57,7 +57,7 @@ class MetasploitModule < Msf::Exploit::Remote
     timeout = datastore['ListenerTimeout'].to_i
     loop do
       break if session_created? && datastore['ExitOnSession']
-      break if timeout.positive? && (stime + timeout < Time.now.to_f)
+      break if timeout > 0 && (stime + timeout < Time.now.to_f)
       sleep(1)
     end
   end