Added ConfigManager to preserve some values. Fixes #221
Added exception checking into ConfigManager
Remade test_config_manager
gui: Fix some python2/3 incompatibilities
Fix some unicode encode/decode errors in PY2
Remade test_config_manager again
Merge pull request #235 from jkoncick/master

Added ConfigManager to preserve some values. Fixes #221. 

Also fixed some py2/3 and unicode encoding issues.
Manual page updates
Fixes #237: Detection for missing DISPLAY and test suite
Import gui when all environment properly set
Merge branch 'master' of https://github.com/phracek/devassistant

Conflicts:
	devassistant/gui/__init__.py