GET EXTENSION

Use modman Linux | Windows :

cd magento_root/
modman clone http://fgit.fgct.net/vankhoa/M2OverrideCreateInvoice.git
modman deploy M2OverrideCreateInvoice

Use git:

git clone http://fgit.fgct.net/vankhoa/M2OverrideCreateInvoice.git
cp M2OverrideCreateInvoice/* magento_root/

INSTALLATION

bin/magento setup:upgrade