* Moved implementation of the methods to the `cpp` file.
* Added `DebugCount::Flag(s)` and `DebugCount::configure(name, flags)`.
* Moved from `QMap` to `std::map` (order is important here).
* Used `QStringBuilder` for concatenations.
* Used `QLocale` for formatting (adds separators).
* Added `DebugCount::Flag::DataSize` for data sizes in bytes (and fixed language to English).
* Used `DataSize` for image sizes (maybe this should be moved somewhere else?).
* Added copy button to popup.
* Fixed Image usage reporting being eight times too large (could be another PR, but honestly it's four characters).