More tweaks

[bakert]

• Avoid broken images for series with no logo uploaded
• Apply fixes from StyleCI
• As much of PSR12 coding standard that phpcs can do automatically
• Centralize session_start in lib.php instead of having to put it in every file
• Remove no-longer-used sidebar.php
• Remove unused function params
• Refactor eventreport into a slightly saner style
• Remove unreferenced old 2013 bracket page
• Don't emit header twice on event report page
• Attempt to further standardize times for human consumption
• Remove now-unused time formatting js stuff
• Banish all remnants of (deprecated) strftime
• Bring start time down on its own line to make room for event title
• Get rid of rather flimsy out of service mechanism
• Convert homepage to using page helper function
• More homepage improvements
• Clean up some old comments
• Use our new standarsized time module for next event of each series