Edit "not outputting the mixin"

Change "around" to "after" to match example.
Merge pull request #119 from marcstober/patch-3

Edit "not outputting the mixin"
Add some info from the readme
Escape backticks properly

Fixes bad Markdown on GitHub.
Merge pull request #120 from ZDroid/code-syntax

Escape backticks properly
Remove `-moz-` prefix for `box-shadow`

Only Firefox 3 requires `-moz-` prefix for `box-shadow`, so adding `-moz-` to `box-shadow` is such a bad example.
Merge pull request #121 from ZDroid/redundant-moz-prefix

Remove `-moz-` prefix for `box-shadow`
guis-for-less.md: fixed Crunch screenshot.
third-part-comilers.md: added link to Less Ports (inspired by #117).
Explicitly declared HSL-tied functions as operating in the HSL colour space.