fix(button-fab): added box-shadow for activated fab buttons
fix(button-fab): added box-shadow for activated fab buttons

Removed the use of !important so the activated class would be applied,
added sass variable for it. Closes #392

janglednerves/ionic,AbraaoAlves/ionic,manucorporat/ionic,alan-agius4/ionic,driftyco/ionic,TillaTheHun0/ionic,AbraaoAlves/ionic,joshesp/ionic,janglednerves/ionic,jarrodkoch/ionic,driftyco/ionic,jhlee8804/ionic,janglednerves/ionic,alan-agius4/ionic,manucorporat/ionic,cambronjay/ionic,AbraaoAlves/ionic,jhlee8804/ionic,dennybiasiolli/ionic,driftyco/ionic,cambronjay/ionic,alan-agius4/ionic,TillaTheHun0/ionic,dennybiasiolli/ionic,janglednerves/ionic,alan-agius4/ionic,joshesp/ionic,driftyco/ionic,AbraaoAlves/ionic,jhlee8804/ionic,jarrodkoch/ionic,manucorporat/ionic,dennybiasiolli/ionic,jarrodkoch/ionic,cambronjay/ionic,joshesp/ionic,manucorporat/ionic,driftyco/ionic,jhlee8804/ionic,TillaTheHun0/ionic,manucorporat/ionic,alan-agius4/ionic,cambronjay/ionic,janglednerves/ionic,joshesp/ionic,brianespinosa/ionic2-sass,dennybiasiolli/ionic,alan-agius4/ionic,AbraaoAlves/ionic,jhlee8804/ionic,TillaTheHun0/ionic,jarrodkoch/ionic,cambronjay/ionic,jarrodkoch/ionic,dennybiasiolli/ionic