Clarify license 

There was a change that said "Changed license from GPL to LGPL", but it just added the LGPL without removing the GPL. This makes the licensing a bit ambiguous. I'd love to give this a shot, but in a project which is LGPL, but not GPL, compatible.

Thanks,

https://github.com/MagnusS/Java-BloomFilter/commit/83ec16eb387bdd1beb21e7927f1d5cbb46cf8fde
