Fixed typo in clock.runAll error

Error would previously say `"Aborting after running 1000timers, assuming an infinite loop!" (notice the lack of space between `1000` and `timers`). Adding a space there.

src/lolex-src.js

@@ -551,7 +551,7 @@
                 clock.next();
             }
 
-            throw new Error("Aborting after running " + clock.loopLimit + "timers, assuming an infinite loop!");
+            throw new Error("Aborting after running " + clock.loopLimit + " timers, assuming an infinite loop!");
         };
 
         clock.runToLast = function runToLast() {