add spell check like "Did you mean ?" for commands

samples expain it ;)
````
>>> superadmin.says('!pputgroup')
sending msg to God: Unrecognized command pputgroup. Dit you mean putgroup ?
````
```
>>> superadmin.says('!yhel')
sending msg to God: Unrecognized command yhel. Dit you mean help ?
```
The existing soundex and getStuffSoundingLike() implementations yielded poor results. In my tests with the code from Peter Norvig was the result always correct. By the way, an interesting read: http://www.norvig.com/spell-correct.html