Refactoring + deprecation fixes
Introduce ScreenshotBackend
interface with concrete implementations ScreenshotBackendShell
and ScreenshotBackendX11
, moving most of screenshot-utils.c
contents there, as the first step towards #89
Area selection still remains.
Fix most of the deprecations, ignore the few in X11 backend that require significant effort to fix. Enable deprecation warnings.
Edited by Alice Mikhaylenko