Some LESS parsers will get confused with the lack of file extension.
It's better to be explicit and in alignment with recent change in core
I379334d7729e587a2a00.
It was already weirdly mixed in this repo with some imports featuring
extension and some not.
Change-Id: Ib208607c850fa2492b13cd3d449c04ebc2c21a01
Changing the way Echo's front-end architecture works to work with
model-view-controller methodology.
Change-Id: I97862402c41bc04dd41cd08d79f19ff677340249
