PMPS-67 refactor payment.php and configurationHandler.php
PMPS-67 refactor validation.php and configurationHandler.php
PMPS-67 use '  instead of "
PMPS-67 refactor webHookEndpoint
PMPS-67 refactor pigmbhpaymill.php
PMPS-71 show all valdation errors
PMPS-75 : edit sturkture; add licence information
PMPS-75 : fix security standards
PMPS-75 : fix errors
PMPS-75 : fix errors
PMPS-75 : fix errors
PMPS-75 : fix errors
PMPS-75 : fixed errors
PMPS-75 : adjust code for presta core integration
PMPS-75 : added registerlink to config
release 1.5.0
adjust date for changelog
adjust date format