v0.16.6

• Content packs updated, bulk of broken exercises fixed and all languages rebuilt (and should be re-downloaded), pay attention to a couple of known issues!
• Allow logins during LOCKDOWN #5117
• Remove RPI warning message about max number of concurrent downloads, there’s no longer a limit on small platforms #4982
• Make ROOT_DATA_PATH consider the KALITE_DIR environment variable #5143
• Restore downloading on RPI w/ m2crypto: Unbundle requests and use requests.get instead of urllib.urlretrieve #5138
• Docs: Add warning message on KA Lite windows application docs #5137
• Treat socket.error as if no server is running #5135
• Docs: Connect to ka-lite on IRC #ka-lite (Freenode) - #5127
• Notify student when all exercises in a series are completed (level has been mastered) #4875
• Use current year in parts of footer #5112
• Handle socket.error: Fix some cases where KA Lite fails to start due to a previous unclean shutdown #5132