2.1.4, released 2008-05-18
! DefinitionCacheFactory now can register new implementations
! CSS properties are now case-insensitive
! Encoder optimized with valid UTF-8 input
! HTML Purifier's URI handling is a lot more robust, with much stricter
  validation checks and better percent encoding handling.
- Colors missing # but in hex form will be corrected
- CSS Number algorithm improved
- Autoclose now operates iteratively, i.e. <span><span><div> now has
  both span tags closed.
- Fix bug with trusted script handling in libxml versions later than 2.6.28.
- Fix bug in comment parsing with DirectLex
- Fix bug with rgb(0, 1, 2) color syntax with spaces inside shorthand syntax
- HTMLPurifier_HTMLDefinition->addAttribute can now be called multiple times
  on the same element without emitting errors.
- Iconv uses set_error_handler instead of shut-up operator
- Add protection against imagecrash attack with CSS height/width
- HTMLPurifier::getInstance() renamed to HTMLPurifier::instance() for consistency
- Fixed bug with fallback languages in LanguageFactory