Merge branch 'release/4.1.2' into develop
Handlingfee express as percentage shouldn't include shipping.
reformated source
WIP set up module for se, no
Handlingfee as percentage based on subtotal only.
moved handling_fee attribute from invoice to handling_fee module
Multiple invoice fees working
Removed unneeded method name reference.
Only add invoice fee rows in order total when invoice payment has been selected.
removed ability to specify invoice fee as percentage.
Turned on ability to enable/disable invoice fee.
Updated documentation on invoice fee specified per country.
Merge branch 'feature/WEB-260' into develop
added notes on upgrading to 4.2 to documentation
bumped version to 4.2.0
Merge branch 'release/4.2.0'