Update bloomfilter.js
Update bloomfilter.js

Buffer size is 8 times larger than required.

Reasoning:
   'var n = Math.ceil(m / 32);' <- n is size in double words
   ArrayBuffer takes size in bytes. Convert double word size to byte size = multiplying by 4.

Current code converted double word back to bits.
beni55/bloomfilter.js,SillyKnight/bloomfilter.js,mcanthony/bloomfilter.js,WatchBeam/bloomfilter.js,jasondavies/bloomfilter.js