[x] Add a post endpoint to send a file called /mappings/load
[x] Only connected users can send a file (the apikey request parameter is mandatory), they will the creators of the mappings
[x] Mappings within the file will be created and saved for those that are valid
[x] Mappings within the file that are not valid will not be saved, the index of the errounous mapping will be listed in the response with their errors.
Requirement
/mappings/load
apikey
request parameter is mandatory), they will the creators of the mappings