GitLab

* Fixed "Cursor Positions on Shared Whiteboards are Inconsistent".

The main fix is in the method cursor_point_to_space in
public/javascripts/spacedeck_whiteboard.js.

The calculation of the coordinates of the mouse pointer from absolute
window to the whiteboard space coordinates was incorrect.

There were a number of dependencies on this method which were updated
as a result.

One side-effect was that the div for the lasso tool needed to be
moved inside the div for the whiteboard.

* Fixed minor panning calculation problem.  Works now!

* Keep the colors between drawing multiple scribbles and arrows

The color is changed back to black on every new drawing. Now the color is kept. If there is no color is set, then there is a fallback to the black stroke as before.

* requested changes
Co-authored-by: togir <gitcatch@weiler.rocks>

* The MongoDB/Mongoose data storage is removed in favor of Sequelize. This abstracts over SQLite or RDBMs like PostgreSQL and MSSQL. The default is SQLite, which significantly simplifies deployments in end-user environments.

* As Spacedeck now has no more mandatory server dependencies, we can wrap it in Electron and ship it as a desktop application.

* Removes docker-compose.yml

* First version of import UI