Revert "Revert "Add support for large integers""

[themasch]

Reverts themasch/node-bencode#50

so here we start the new diskussion about #44 after reverting it in #50 ;)

[themasch]

I really like the idea of making. I'm currently failing to understand how this could work for decoding but encoding looks pretty good. It also enables lots of other use cases like the binary-key-dict one or real booleans etc. We/people could release bencode-* plugins that extend/replace types in bencode. :+1: from me.

[jimmywarting]

New ways introduced 1n and BigInt(1)

[ThaUnknown]

https://github.com/webtorrent/node-bencode/pull/150