Some mistakes found when packaging for Debian:
- Remove trash from rules and enforce hardening.
- Use the same licensing from Debian package to avoid a misinterpretation
from FTP Master.
- Fix target variable in debian/rules
* adapt UI for i18n
* add placeWidgets() helper function to ease translation
* add hint about Transition Matrix plugin on Transition tab
* translate
* rework UI of file tab
* write status of plugin to scene info file
* fix MacOS CI issues due to QT deps
* adjust to new name of deps archive
* use MACOS_DEPS_VERSION instead of OSX_DEPS_VERSION
* disable python dependency during build