trivial: Update the example spec file
Add as_utils_get_string_overlap()

This is needed for future code.
Do not add empty font metadata
trivial: Do not try to save screenshots if no ScreenshotDir set
trivial: Print warnings before writing metadata files
Merge apps with overlapping IDs from the same pkgname

This should work for a lot of fonts and also applications where there are things
like level editors and different runtime versions.