Don't load line items to calculate the amount, use the database to obtain the result
Fix prev next icons on datepicker

apply a .fa class so font-awesome icons work fine

Fixes #4876
fixes #4866 (wrong iso3 code for romania)

fixes #4875
fixes #4874
Fix pagination for taxons

Fixes #4873
Fixes #4854
Update shipment in proper chronological order

Every time the selected shipping rate has changed as a shipment cost
change should be propagated through order totals and states

About #4845