Fix bug in 16e273944c

A `<` had accidentally been replaced with a `>`. Doh!
Enhance performance and simplify the API

Yet a full iteration of the array of elements has been removed. To easier
implement this, I made some sane simplifications to the API.
Merge branch 'develop' into huffman

Conflicts:
	extension/packages/huffman.coffee
Minor cleanup
Merge pull request #156 from lydell/huffman

Huffman fixes