OZP-10: Migrate displaying a dashboard.
> OZP-264: Update themes
> OZP-495: Migrate widget header functionality for editing the name.

1. Did default theme to look like OWF 7 for all the layouts.
2. Added handles to all sides of desktop widgets and constrained the resizable area to the pane.
3. Added logic to DesktopPane to check if a resize causes any widget headers to overflow outside of the pane, if so it moves the widget header up until visible.
4. Used X-editable library to implement widget header name editing.
OZP-499 Updated README.md