v0.18.0

Go team! New Release!

To upgrade: yarn upgrade

Changes: v0.17.2..v0.18.0

Documentation: http://symfony.com/doc/current/frontend.html

Highlights:

• Added Encore.addAliases() and Encore.addExternal() shortcut methods
  #217 via @Lyrkan

• Fixed hash lengths - normalized all to 8 - #216 via @Lyrkan

• Added CoffeeScript loader - #201 via @harentius