New, open and save functions moved from the old code;
Added file extension to the application state.
Ribbon menu refactoring: added two button types (common and open).
'New' function moved from the old code.
Home ribbon tab: fixed `colors` layout;
Fixed primary/secondary color buttons' style.
Removed unused code
Canvas now properly determines mouse position.
Implemented red tics on rulers block.
Improved canvas markup, rulers markup, red ticks (in rulers) positioning etc.
Crosshair and luma_picker images moved from old folder to the lib's folder.
Crosshair and luma_picker images replaced by svg.
Removed obsolete tag
Color picker fixing
Color palette picker now hides on clicked-mouse move (i.e. if user clicks and moves picker)
Fixed color converting issues
Colorpicker improvement
Predefined colors now clickable
Copy predefined color on select by value
Colorpicker renaming
Revert "Colorpicker renaming"

This reverts commit e85fc2a6be998c78e748cf9fd2d3f379378a2ec7.
Revert "Revert "Colorpicker renaming""

This reverts commit aade81efbd395836b45fcbbce64866b9188899b4.