Fix validation issues with missing required fields

Closes TOMP-WG#174

scenarios for support (TOMP-WG#157)

authored-by: Edwin van den Belt <EvdBelt@dat.nl>

Merge pull request TOMP-WG#154 from ARBaart/hotfix-0.5.1

Hotfix 0.5.1 remove double description fix parameter location of journal-entry

Merge pull request TOMP-WG#145 from edwinvandenbelt/release-0.5.0

Release 0.5.0 - Clara

Version 1.2

Adds license
Major update to the payment module
Updates to planning and booking modules in accordance with changes to the payment module

Version 1.1.2

Version 1.1.1

Version 1.1

Major update to the planning, booking and trip execution modules
General overhaul of the API to be closer to a REST API
Split of API endpoints between TO and MP side

Version 1.0.8