Global error handling & debug mode

[DarTar]

This handler should:

• monitor all errors or warnings from the wiki;
• display messages in a consistent way;
• dispatch notifications when needed and depending on specific configuration settings.

A debug mode should display, when activated, more information about the i/o of each component (actions, handlers etc.), on top of the existing SQL debugging, to wiki admins. A new class (.debug) was added to 1.1.6.4 for the styling of debug messages (hardcoded for the checkversion action).

Related tickets

• #553 Responsibilities and "contract"
• #439 DB connection errors

[DarTar]

Trunk contains basic utilities for logging and debugging. Debug messages are currently generated in a very crude way, e.g.: if ($debug) echo "default 3rd-party component URI paths...<br/>\n"; We should use a simple function instead, every time this output is needed and the debug flag is active, wrapping the error message in a paragraph with the debug class (already in trunk's stylesheet).