feature: ":extend()"

[jonschlinkert]

Badly in need of documentation.

[jonschlinkert]

less/less.js#1460

[Tyriar]

I can help out with some documentation if you would like.

[jonschlinkert]

@Tyriar great, thanks! any help is appreciated. My wife and I are expecting a baby any day now. So I'm busy preparing, but in a couple of weeks I'll be back at full speed. What I'll try to do in the meantime is update the readme and contributing.md with some general guidelines. I'll ping you when that's done in case you're interested in contributing something.

[Tyriar]

@jonschlinkert sounds good, and congratulations!

[jonschlinkert]

thanks!

[lukeapage]

feel free to rip off my blog post on them

http://www.scottlogic.com/blog/2013/03/08/extends-in-less.html

[jonschlinkert]

@lukeapage great, thanks! I'll make sure to add links to the blog post as well

[lukeapage]

I'm going to merge what you've written (in 2 places?), what @SomMeri has done https://github.com/SomMeri/less4j/wiki/Less-Language-Extends and something of myself