refactor(toolbar): rename no-shadow to no-border for md mode
refactor(toolbar): rename no-shadow to no-border for md mode

BREAKING CHANGES:

Renamed `no-shadow` attribute for Material Design header, footer, and
tabs to `no-border`. This is the same attribute used by iOS mode.

brianespinosa/ionic2-sass,driftyco/ionic,TillaTheHun0/ionic,joshesp/ionic,alan-agius4/ionic,alan-agius4/ionic,dennybiasiolli/ionic,alan-agius4/ionic,alan-agius4/ionic,joshesp/ionic,driftyco/ionic,dennybiasiolli/ionic,alan-agius4/ionic,TillaTheHun0/ionic,dennybiasiolli/ionic,driftyco/ionic,TillaTheHun0/ionic,TillaTheHun0/ionic,dennybiasiolli/ionic,dennybiasiolli/ionic,joshesp/ionic,driftyco/ionic,alan-agius4/ionic,driftyco/ionic,joshesp/ionic