Initial gui tests using Dogtail and Behave
Added ask_input with tests
Ask for user name and e-mail for git

Fixes #236
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