This outputs YAML in a string that is suitable for use in regexps
and string replacements, as well as complete files. It is therefore
explicitly set up to avoid writing out headers and footers.
This is a key piece of the ongoing `PUBLISH` _config.yml_ migration. There was uneven implementation of which YAML parser to use, and that could lead to bugs where one parser might read a value one way, and a different parser will read the value a different way. I wanted to be sure that YAML 1.2 would always work.
This makes all code that handles config files use the same `ruamel.yaml` parsers. This only touches other usages of YAML parsers when there is overlap. This does not port all of _fdroidserver_ to `ruamel.yaml` and YAML 1.2. The metadata files should already be YAML 1.2 anyway.
# Conflicts:
# fdroidserver/lint.py
