improve unit test to check for another edge case re:breaking ties
weight single class selectors based on their distance from the target element since they all have the same specificity value.
Merge pull request #573 from amro/fix_selector_weight

Properly order single single class selectors and add a test
1.6.6 updates
Merge branch 'release-1.6.6'
sort the array in place so single class cascades from ancestors work
Restored IVAR used by DTRichTextEditor
Restored IVAR used by DTRichTextEditor
Merge branch 'master' into develop
added unit test for #498
Merge branch 'od/issue_498' into develop
Merge branch 'develop'
Merge pull request #575 from amro/fix_single_class_cascading_selectors

Sort the array in place so single class cascades from ancestors work
handle cases where the current and terminal selector part are the same. remove list workaround that's no longer necessary.
removed workaround for adjusting list bullet pre-CSS-cascading #574
Added list bullet unit test #574
simplify conditional and add comment
Merge pull request #576 from amro/fix_list_style_cascade

Fix cases where the current and terminal selector parts are the same
removed crash test from MacUnitTest
Added unit test for mixed list prefix issue #574