In some environments you may want to have logs but not have them stored
in the default location or may want a different logging format.
This event allows plugins to do that.
Log facitlities can now be disabled. By default only debug is disabled.
It might make sense to by default disable deprecated as well?
Debug logging is now independend of the allowdebug method. allowdebug
was often used in two ways: for displaying errors directly to the user
and for logging to the debug log. Now it only controls the former.
This introduces a logger mechanism and a new data/log directory. This is
a first proof of concept. It's built on top of the new global error
handling mechanism
Things to discuss:
* should we adopt PSR-3 somehow? if yes, how and should plugins be able
to drop-in other psr3 loggers?
* how to configure which facilities shall be logged?
* should we implement a log deletion feature?
* is the log format sensible?
* should we implement a log viewer admin plugin?
* should logging trigger events (it should maybe replace the
deprecation event)
Andreas Gohr