Dothebackup

-------------------

Fix
~~~
- Add typing as dependency. [Marvin Steadfast]

-------------------
- Print stdout from commands in debug more. [Marvin Steadfast]
- Added borg check command. [Marvin Steadfast]
- Dothebackup return itself an error exit code. [Marvin Steadfast]

If one job failed it will not just write this to the job logs it also
will exit with a different exit code.
- Fixing import order in tests. [Marvin Steadfast]
- Added typing and plugin for borg backup. [Marvin Steadfast]
- Switched from ``arrow`` to ``pendulum`` [Marvin Steadfast]

-------------------
- Replace invalid characters in logging. [Philipp Weißmann]
- Working on Jenkinsfile. [Marvin Steadfast]
- Added Jenkinsfile. [Marvin Steadfast]

-------------------

Fix
~~~
- Logs finally rotate. [Marvin Steadfast]

forgot to call the rotate function in the runner and fixed a bug caused
by the log numbering order. logs are now numbered like::

foo.log
foo.log.0001
foo.log.0002

-------------------
- Testing and no installations for old python versions. [Marvin
Steadfast]

added more python versions for local tox testing. installations on
python versions < python 3.3 will be aborted in setup.py.
- Logger module. [Marvin Steadfast]

added logger module for better logging of the jobs stdout. it keeps
track on rotating old logs and writing to the right logfile.

the logging part of the config changed. a example::

logs:
dir: /var/log/dothebackup
keep: 10
backup:
...
...
...

**keep** defines how many log files to keep.

-------------------
- Adds log for startup and finishing dothebackup. [Philipp Weißmann]
- New changelog. [Marvin Steadfast]