Fix bug where configuration was not being updated with passed-in parameters
Switch toutf8 to encode
Type of EngTagger needs to be consistent
Limit memoize cache size to avoid effective memory leak
Use lru-cache gem for bounded space memoization
Replace globals with scoped constants

Remove hpricot based tag stripping, doesn't seem like the responsibility
of this gem.
Remove unused kconv require
Add code for release to gemfury
Merge pull requests from upstream.