Introduces "long edge" and "short edge" options to resize an image. The GUI is made such that the relevant spinboxes only appear for the selected option. Unrelated values (e.g. for box-mode) are not updated.
Replaces the following deprecated Gtk classes throughout the codebase by their non-deprecated counterparts. Style, HBox, VBox, HPaned, VPaned, HScrollbar, VScrollbar, VSeparator, HSeparator, Stock, Table, VScale and HScale.
It was impossible to export a small crop upscaled to 1200px wide to
demonstrate the effects of noise reduction, so I bumped the max scale
from 4 to 16 (to match the 1600% main preview max zoom).
This adds a little helper class to `guiutils.*` that unregisters
in-flight idle functions queued by `IdleRegister::add()`. It's best
to call `IdleRegister::destroy()` in the destructor of the class
owning the `IdleRegister` instance. Otherwise make sure, it is the
last member which will be deleted first.
`Resize` now makes use of this new facility in `setDimensions()`, which
also fixes#3673.
