AltGr+M doesn't create a µ

[siebrand]

Logged at https://bugzilla.wikimedia.org/45149. There's also some code there: http://bug-attachment.wikimedia.org/attachment.cgi?id=11811

Diff is small, so copying it here:

diff --git a/lib/jquery.ime/jquery.ime.js b/lib/jquery.ime/jquery.ime.js
index 670aa93..f5918e2 100644
--- a/lib/jquery.ime/jquery.ime.js
+++ b/lib/jquery.ime/jquery.ime.js
@@ -924,7 +924,7 @@
function isShortcutKey ( event ) {
// 77 - The letter M, for Ctrl-M
// 13 - The Enter key

•   return event.ctrlKey && ( event.which === 77 || event.which === 13 );
  

•   return event.ctrlKey && !event.altKey && ( event.which === 77 || event.which === 13 );
  

  }

  function isDOMAttrModifiedSupported () {