Don't use array_merge with numeric keys, since the numeric
keys from the first array are overwritten by those of the second.

See also commit 87c73b46531db18.
Various minor changes (formatting, comments, etc.) no functional
changes intended.
Move contest{problem,team} table to keep table list sorted.
Repair contest simulation script by readding option parsing
and add option to specify contest (defaults to single active one).
Uniform layout of SQL example data.
Fix mysql example data.

- contestproblem table was added twice
- disable foreign key checks while importing examples
Improve error message when parsing contest starttime fails.
Fix problem shortnames.
Fix example data: make one contest public and the other not. Also set deactivatetime when upgrading to something
All teams are now "part" of every public contest and the API shows non-public contests if authenticated as a team or jury
Merge remote-tracking branch 'upstream/master' into GEWIS-online-judge

* upstream/master:
  All teams are now "part" of every public contest and the API shows non-public contests if authenticated as a team or jury
  Fix example data: make one contest public and the other not. Also set deactivatetime when upgrading to something
  Fix problem shortnames.
  Improve error message when parsing contest starttime fails.
  Fix mysql example data.
  Uniform layout of SQL example data.
  Repair contest simulation script by readding option parsing and add option to specify contest (defaults to single active one).
  Move contest{problem,team} table to keep table list sorted.
  Various minor changes (formatting, comments, etc.) no functional changes intended.
  Don't use array_merge with numeric keys, since the numeric keys from the first array are overwritten by those of the second.