fix #893

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
changelog for #893/e25d8d0

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
Set TIMEZONE to UTC by default

 * helps prevent bugs like #893 (461c5f5 made non-TIMEZONE people break,
   it was the reverse before)
 * could help us get rid of some useless code for testing whether
   TIMEZONE is set (we can happily crash on people that have an invalid
   value there)
 * we assumed UTC (incorrectly called GMT in conf.py.in before) anyways,
   so nothing changes in output
 * config options set to `None` by default suck (we should have a
   singleton named UserIsAnIdiotAndWeShouldCrashHorribly (or something
   like this) and crash whenever any config value is set to it (i.e. we
   should have sane defaults where we can, and required config values
   where we can’t)

Done with @ralsina’s blessing.

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
document 623d828e

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
623d828e refinements

 * bullet point 2 (now useless code gone) is applied
 * import_wordpress and test_rss_feeds acknowledge the change

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
flake8

Signed-off-by: Chris “Kwpolska” Warrick <kwpolska@gmail.com>
Persist and re-use last RSS feed build date.
Hack to repair the "guid" damage, that might flood the planet.
Added support for tag clouds to site theme.
Use absolute URLs for relative URLs that go upwards.
Preserve mode when using inplace filters that use a temporary file.
Use "Nuitka" logo colors for tag cloud, added padding to border.
Move page source link to footer.
Use logo image over title in navbar
Minor logo changes
Disable locale related warning.
Fixup permission issue