Move constants to Liquid class
Rename exception file
Update PHPDoc, code style, set todos
Remove passing params by reference
Load tags with namespaces
Fix deprecated preg_replace call
Fix tag search path
Detect class name with reflection
Pass tokens as reference
Avoid strict standards errors
Remove several todos
FileSystem interface
Drop todos
Filterbank todos
Leave only tags in Tags directory
Remove tag names todos
Tag case todos
If tag todos
Fix cache class
Replace to_string with __toString