CSSTidy Code

One more test and bugfix

Unit test cleanup and more unit tests + bug fix for number optimisation

- Add discard_invalid_selectors cfg and functionality; this fixes some of the duplicate combinator problems
- Minor comment formatting changes
- SETTINGS and FULLEXPECT support added to csst tests

Minor formatting changes:
- Compress extended if/else statement to indicate chaining
- Remove trailing ?>, it's not necessary in PHP!
- Add a custom harness for all unit tests

Add a continue to bad hexadecimal code correction, otherwise value is clipped to zero.

Per Flo's emailed consensus, added change to LGPL (2.1), authorship for myself, and updated copyright notices to 2007

Added identity tests (for speed and accuracy) in cases where I knew it would be as safe as an equality test

FS#144 — !important rule

FS#140: Fixing Values of Invalid properties

FS#143: Save some more bytes