remove some dead code

Author: isaacs

lib/mocha.js

@@ -17,16 +17,6 @@ var tapStack = [ t ]
 var level = 0
 var suiteStack = []
 
-var running = false
-function run () {
-  if (running)
-    return
-  running = true
-  process.nextTick(function () {
-    rootSuite.run()
-  })
-}
-
 function describe (name, fn) {
   new Suite(name, fn)
 }