Implement some extra methods of determining the current user/group
Be more accurate about the value of boolean constants
Remove the redundant `QM_Util::wpv()` method
Move the loading of dispatchers to the `plugins_loaded` hook so plugins can add their own
Restore the default PHP error handler at an appropriate time
Rename the `active()` dispatcher method to `is_active()`
Cache the value of `QM_Util::standard_dir( ABSPATH )`
Remove 'error_handler' from the trace

If `error_handler()` is in the trace, QM fails later when it tries to get `$lowest['file']` in `get_filtered_trace()`
Add a CONTRIBUTING file