Reject deleteMessages for >2 week old messages (#163)
Reject deleteMessages for >2 week old messages (#163)

* Reject client.deleteMessages if it tries to delete a >2 week old message.
- As per hammerandchisel/discord-api-docs#208

* Requested changes
- Remove parseInt
- Precompute 2^22
- Change rejection message

* Removed braces as requested
- (╯°□°）╯︵ ┻━┻

* More requested changes
- ABAL I SWEAR

Datamats/eris,abalabahaha/eris,Flyy-y/eris,briantanner/eris