training entry more checks in cgi

[kikmann]

done in js

• [ ] to be done in cgi:

qqtodo: some sanity checks on the input data

startdate & trainingtype mandatory

# distance, heightmeter, duration must be numbers
# teamtraining can be "", "virtual", "inperson"
# teamdistance, teamheightmeter, teamduration must be numbers
# teamefforts must not be greater than individual efforts
# distance/heightmter/duration are required depending on training type
# trainingtype must be of the allowed types of the challenge

[kikmann]

• [ ] also for modify