Pympress

- Improve locale handling and translations, including adding new Chinese and Italian translations, and translation of menu items
- Fix display of shortcuts in shortcuts display window
- Improve shortcuts to erase in note scribbling
- Allow beamer notes on separate pages with a `notes:` prefix to the page number, e.g. with `\addtobeamertemplate{note page}{}{\thispdfpagelabel{notes:\insertframenumber}}`
- Allow beamer notes on every second page (no automatic detection possible)

Fix errors in compiling catalogs with gettext during build process

- Make “next slide” a grid of 1-16 next slides
- Allow dynamic layout editing from pympress (rather than modifying the config file manually)
- Make annotations editable
- Allow to save modified PDF files
- Automatic next slide and looping
- Support auto-play (some annotations, e.g. movie15 / ConTeXt)
- Make gstreamer default media backend on macOS and Linux
- Limit to python 3.4+ to do some code modernization

- Make “next slide” a grid of 1-16 next slides
- Allow dynamic layout editing from pympress (rather than modifying the config file manually)
- Make annotations editable
- Allow to save modified PDF files
- Automatic next slide and looping
- Limit to python 3.4+ to do some code modernization