Convert CHANGELOG to Markdown

+ add release dates
Fix typo in rhino. Fixes #896
Fix error output and extract a helper object for lessc related methods

- Fixed a bug, which prevents colors from being set in error messages.
- Created a helper object for lessc methods and moved the stylize function
  into it. Changed test/less-test.js and lib/less/index.js to use new methods.
- Removed duplicate definitions of the stylize function.
Add some content to lessc help

Added some details to lessc and extracted a printUsage method.

Fixes #817
remove process.exit calls as they do not guarentee a flushed stdout
Fix mixin calls being recognised as mixin definitions when arguments contain spaces and interpolated strings. Fixes #901
Fix #423 by preserving order of link/style elements

Appending generated css to the head element is confusing because it
changes the order of style declarations. If there are regular css link
or style elements after the less link element, less declarations with
equal specificity will override css declarations that come later in the
document.

This change preserves the original order by inserting the generated css
immediately after the less link element.
Added: red() green() and blue() functions, with tests.
Don't try to use variable values that do not exist on the browser. Fixes #190.
fix #31 and #406

Conflicts:

	lib/less/parser.js
Add whitespace tests for previous commit - newline in selectors
Fix other whitespace issue brought up in #406
Remove UTF8 BOM -  fixes #650
Soft light blending mode added.
8 more blending modes added: multiply, screen, overlay, hardlight, difference, exclusion, average & negation.
Add parent selector to user variable
Fix error unit tests to run on any computer
Revert commit mistake
add support for utf-8, fixes #396 (this time less messy commit)
added fraction support to round function