Matches lengths with just 0 or 0-with-unit as duplicates

Most of this work was by @mduvall

Some stackoverflow discussion: http://stackoverflow.com/a/935113/410759

refs: #42, #32
Disables color support on windows env where ruby < 2.0

I've gotten a report that color support on windows && ruby 2.0 just
works. So let's try and only disable it in window && ruby 1.9

refs: #48, #44
Fixes bug where unquoted url(data..) wasn't being parsed

refs: #46
Fixes semicolon parsing within a url

The dynamic block is pretty hookey, but I think it might work. It is
doing a manual lookbehind to see if there is an open parenthesis. Not
the prettiest code, but it should work.

It is also downcasing the base64 encoded data, which could cause
collision issues, but encoded images are so uncommon that I don't think
it will be a big issue. For now.

refs: #46
Revert "Fixes semicolon parsing within a url"

This reverts commit 828d4c801a5a9266d261ae2a770d1991cb46303b.

While this fixes the parser, it tanks performance. Need to figure out a
better solution
Adds support for LESS css

This support behaves very similar to the SASS support. It will attempt
to compile the css prior to checking for redundancies.

For c-versions of ruby, therubyracer is required. For jruby,
therubyrhino.

More information can be found at http://lesscss.org/

refs: #52, #10
Fixes semicolon parsing within a url

This is a different implementation than
828d4c801a5a9266d261ae2a770d1991cb46303b

It is also downcasing the base64 encoded data, which could cause
collision issues, but encoded images are so uncommon that I don't think
it will be a big issue. For now.

refs: #46
Fixes massive performance issue when using eql?

Not sure if it's due to constructing the array and calling #hash on it
or what, but the previous implementation is terrible on performance

refs: #42, #32
Bumping version to 1.2.0 for release
Adding _site to gitignore
Adds --require switch to allow user specific config

This will allow people to configure bundler, sass plugins, special
configurations, etc.

refs: #54
Deprecates --compass-with-config

I knew that was a bad decision. --require will be a lot simpler

refs: #54
Parses and ignores @import statements

Users will need to run csscss on those specific files.

This also fixes a bug where comments were being merged with selectors.

refs: #41, #57, #58
Formatting the switches a little
Cleans up some require/abort lines
Adds an experimental flag to ignore sass mixin declarations

Users can now do this with --ignore-sass-mixins.

This is a heavily requested feature. Some users don't care about
duplication coming from sass mixins. So this will inject a special
comment before/after the properties from the mixin and the parser will
ignore it.

This will mess with reporting selector line numbers if I implement that
in the future.

I'm not sold on this being the default yet.

refs: #25, #59
Bumping version for 1.3.0 release
Updates README with --ignore-sass-mixins info
No need for such a long example
whoops