Implementation of a better feedback in the GUI

Summary:
Implementation of a widget to show errors when executing and debugging code:

• A QDialog shows which exception was raised
• All exception are send like strings
• QTable shows types and value previously converted to string now
• New method added to UiController to show critical errors(exceptions) in the GUI

Bugfixes:

• Error when the run action fails and the debugger does not work anymore
• Blocking GUI when the debug process breaks

Fixes T4551

Ref T1625

Test Plan: None

Reviewers: rempt

Subscribers: eliakinalmeida

Maniphest Tasks: T1625, T4551

Differential Revision: https://phabricator.kde.org/D4616