Does a checkout of the full commit history and checks the status
integrity of each subtree using the git-subtree-check.sh provided
in contrib/devtools. Default subtree remotes are defined in the
new file contrib/subtrees.json
Adds a lint job to the CI where we can do sanity analysis on
included files to help spot errors on non-cpp source files
that may cause problems during runtime.
This first job implements contrib/devtools/check-translations.py
that alerts the repository of errors in the translation files in
src/qt/locale. Errors in a translation file are otherwise only
becoming visible during runtime.
