Update the getting started section
Summary:
This patch updated the getting started section
- Added information about the lime ppa and other changes in installation section
- corrected the creating new document section according to the changes in layout
- added new interface image
- some other minor tweaks
Reviewers: scottpetrovic, woltherav, Krita: Manual
Reviewed By: woltherav, Krita: Manual
Tags: Krita: Manual
Differential Revision: https://phabricator.kde.org/D19630
