Always return `true` by default for our PHP error handler to suppress things like Xdebug output
Remove some unnecessary `function_exists()` calls
Show the number of times each PHP error has been triggered
Avoid a big performance bottleneck when performing reflection on closures
Misc tweaks
Further reflection improvements
Misc
New QM_Timer class ready for our profiling
Reinstate the `function_exists( 'symlink' )` check which is needed for PHP 5.2 on Windows. Previously: https://github.com/johnbillion/query-monitor/commit/223d2722dbefd86444dd26da579723d4f255b9c2
Introduce a brutal iron-fisted ruler in the form of `QM_DISABLE` which has absolute power over the kingdom of Query Monitor
Shave a good chunk of wall time off of `QM_Backtrace::filter_trace()`
Make the theme template filename clickable
Display HTTP proxy information when appropriate
A bunch of miscellaneous minor tweaks