Summary:
{F8324215}
Added dialog for SVN Update, SVN Revert and SVN Commit actions.
This dialog is universal and prints everything from stdout and stderr (stderr prints in red).
Supports for "Cancel" action which sends terminate signal to a running process.

Test Plan:
1) Try "SVN Commit", "SVN Revert" and "SVN Update" actions from plugin popup menu.
2) Try "SVN Revert" action from "SVN Commit" dialog.

Reviewers: #dolphin, #vdg, elvisangelaccio, meven

Reviewed By: #dolphin, elvisangelaccio, meven

Differential Revision: https://phabricator.kde.org/D29788