LibreSignage v1.0.3 patch release

This is the final patch release for LibreSignage v1.0.x. This
release includes some bug fixes and small tweaks. Users of v1.0.2
are encouraged to upgrade to either v1.0.3 or preferably v1.1.0
as soon as possible.

This release can be obtained from Docker Hub via the tags "latest"
and "v1.0.3" shortly after the release or built from sources provided
in the LibreSignage GIT repo at https://github.com/eerotal/LibreSignage.
Further instructions are provided in the readme.

Changelog v1.0.3:

- [bugfix]   Fix a bug where slide markup error indicators weren't cleared
             if the slide with the errors was removed. (issue #97)
- [bugfix]   Attempt to fix a bug that caused a memory leak on the
             display page. (issue #101)
This tag has no release notes.