Allow uploading testcases archive in AWS
Wrapped the zipfile upload to catch bad zip files.
White spaces must be a bytes string.

Also, extend the set of white spaces with those defined by Unicode.
Typo in docs.
Fix pep8 warnings.
Simplify interface for java tasks.

Also add a fake updater to issue warning on the changed semantic of
the Java compilation.
Amend documentation for new languages.
Add tests for managed tasks in Java.
Add communication and managed functional tests for Pascal.
Don't allow contest.start and contest.stop to be null
Allow admins to limit the localizations of CWS available to users

Co-authored by Luca Wehrstedt.
Add interface for users to choose CWS localization, overriding browser

Co-authored by Luca Wehrstedt.
PEP8
Fix ambiguity in documentation (database setup)
Add entries to .gitignore
Make the testuite start ProxyService and ScoringService w/o contest
Add docstrings.
Clean code in cmstestsuite

Move definition of check functions outside the start_* functions. Also,
for web servers, check that both the RPC and the HTTP servers are up.
Fix tests

This code was failing since we moved ScoringService among the
contest-agnostic services. On the other hand, ProxyService needs to be
restarted.
Avoid an infinite loop which could jam ProxyService

If an operation with an empty dictionary of entities to create/update
was added to the queue, data[i] could become empty with task_count[i]
still being positive. Therefore no data would have ever been sent (and
thus task_count would have never been reset to zero) but the loop would
also have never yielded to other greenlets, making ProxyService stuck
(and taking up 100% of the CPU).