Improve debile-master and debile-slave logging, with new command-line options.
Merge debile-incoming-* into debile-incoming, with new command-line options.
Merge debile-import into debile-master-init.
Use context manager for debile-master db sessions.
Improve exception logging in sbuild.py when sbuild failes to run
Improve exception logging in debile-master.
Simplify debile-slave loop
Add signal handling to debile-master and debile-slave
Look for config file in XDG directories before falling back to /etc.

* Add command-line options to explicitly select a config file.
  - If not specified look in XDG_CONFIG_HOME, XDG_CONFIG_DIRS, and /etc for it.
* Explicitly create the config object in each process.
* Drop the global config object in debile.utils and debile.slave.
  - Pass the relevant values as arguments to functions that need them instead of having them look it up in the global config.
* Move all "hidden" global objects in debile.master to debile.master.utils, and reduce their direct usage outside of utils.py.
Merge branch 'master' into wip
Improve handling of old jobs when a new source is uploaded.
Force TLSv1
Add sanity checks to debile-master-init
Add sanity checks to debile-master