improve devel call graph
use forked jenkinsapi to configure views to use regex instead of explicit list of jobs
skip binary job when package is not yet in cache
skip default maintainers when package is not yet in cache
only reconfigure jobs if necessary, fix multiple dynamic recipients
improve job trigger checks
set LANG env
add flag to requeue jobs when slave dies
filter queue for devel and release views
add section around upstream project check
wrap all apt-get calls with script which retries in case of known error conditions
Fix format string in binarydeb_job.py: Operator '+' has lower precedence than '%'.
Add a link to the forked rosdistro version to README.md.
Refactor release_job.py by introducing BuildTarget and OSTarget.
Start to refactor configure_release_job by introducing JobValidationError.
Refactor release_job.py.
Fix build_configuration.py: Use type hinting in docstring instead of function annotation.

We cannot use type annotations in these cases because the names of the
containing class, or later classes in the same file, are not defined
at the point in time when the function annotation is evaluated.
Also use docstring instead of function annotation for "generic" types.

According to https://mail.python.org/pipermail/python-ideas/2014-August/028618.html,
using function annotations for this might become possible in the future, though.
Also use docstring instead of function annotation to remove import clutter.
Replace all hardcoded references to https://github.com/ros-infrastructure/ros_buildfarm.git with the appropriate variables.