Add lineman-autoprefixer, lineman-imagemin, and lineman-svgmin plugins.

[erictaylor]

Add the following plugins to the Linemanjs.com documentation, as per @searls request.

https://github.com/Psiablo/lineman-autoprefixer
https://github.com/Psiablo/lineman-imagemin
https://github.com/Psiablo/lineman-svgmin

[searls]

Anyone other than me interested in tackling this?

[erictaylor]

Would also like to see lineman-livereload added to the list as of Lineman@0.33.4.

[erictaylor]

Ignore my comment above about lineman-livereload. Deleted as full support is built into 0.33.4