Remove alpha from contrast calc, see #1724
Add link to docs project in contributing section
Add link to docs project

And add including solutions to bug reports
fix the benchmark less
update the changelog with details of the performance improvements
normalize the base path as well as the filename for sourcemaps. Fixes #1736
Merge branch 'master' of https://github.com/cloudhead/less.js
Merge pull request #1733 from Synchro/master

Remove alpha from contrast calc
Experimental support for "property name interpolation".