Make encoding configurable

[WtfJoke]

The encoding should be configurable. If nothing is configured, the default encoding should be used (encoding = None).

This issue is resolved when the encoding is configurable in the config and a wiki-entry has been made about how to configure the encoding properly with the magic.properties

See discussion #26 (comment)

[WtfJoke]

Wiki-Entry can be found here: https://github.com/WtfJoke/rtc2git/wiki/Encoding

[Cloud-Forge]

Hi,

in shell.py line 23 :
output = outputasbytestring.decode(sys.stdout.encoding).splitlines()
throw an error of the type :

UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe9 in position 224: inval d continuation byte

even though the encoding in the config.in file is not set as utf-8.

To circumvent the issue I had to add :
sys.stdout.reconfigure(encoding=generalsection.get('encoding'))
in configuration.py line 38, so the sys encoding is set properly.