find the index of a buffer in a buffer. should behave like String.indexOf etc.
var bindexOf = require('buffer-indexof');
var newLineBuffer = new Buffer("\n");
var b = new Buffer("hi\nho\nsilver");
bindexOf(b,newLineBuffer) === 2
// you can also start from index
bindexOf(b,newLineBuffer,3) === 5
// no match === -1
bindexOf(b,newLineBuffer,6) === -1