Hygiene: Icon cleanup

Now everything uses box-sizing clean up css so that .icon has
a default dimensions. Make all the icons global and reusable.

Introduce icon-cancel-light and icon-cancel, icon-submit,
icon-continue, icon-photo, icon-clear, icon-back, icon-arrow-up
and icon-arrow-down

Share icons between toggling and drawer

Change-Id: I813bfd76ea2fafa6eebe42cafcbbe1c59856ac2c
Merge "Hygiene: Icon cleanup"