Cursors, Esc to cancel active tool

[olekhshch]

PR description

-- more specific cursors for Circle, Ellipse, Square and Rectangle tools

-- Esc key cancels the currently selected tool. It applies only for Zoom, Rect, Square, Circle, Ellipse, Line, Text, Star, Polygon, and Eyedropper. Cancelation with the Esc key is disabled if pressed in the middle of using those tools (e.g. in the middle of drawing a new circle) to avoid unexpected behaviour;

-- I and B shortcuts for italic and bold text are unavailable if no text element is selected - currently, when pressing those keys nothing happens and other shortcuts (e.g. E for Ellipse) become unavailable until refresh (app throws an error);

-- minor styling changes

[jfhenon]

please fix linter issues.

[olekhshch]

Sorry, my bad, I accidentally ran the linter on the wrong branch before submitting PR 😅 Fixed

[jfhenon]

Brilliant - thanks