* Take scale factor into account.
* Put it in '_onMenuOpenStateChanged' so the max-height will be updated if the monitor size change.
See PanelMenu.Button.
* Import palettes from a .gpl file (one palette for each column).
* Add possibility to use more than 9 palettes.
* Color display names support.
* color.toJSON for svg and drawing saves, color.toString for display.
* A minimum width for the menu, the same as the aggregate menu, in order to prevent the menu with from growing on submenu open.
* A maximum width for uncontrolled content (font, image and drawing names). Same value and same reason.
* Style the font family labels in idle loop to open the submenu fastly.
* Add the drawing gicons in idle loop to open the submenu smoothly.
The color picker use the ["Color Picker" extensions](https://github.com/tuberry/color-picker) if it is available thanks to `pickAsync` "api". In comparaison to the GS color picker, it provides a colored cursor and a menu to adjust the color.
* element.x and element.y are relative to the area, not to the stage.
* Do not hide and do not set opacity to 0 because ibusCandidatePopup need a mapped text entry to init correctly its position.
use `PangoCairo.show_layout_line` instead of `PangoCairo.show_layout`. It is equivalent.
show_layout (doc): "The top-left corner of the PangoLayout will be drawn at the current point of the cairo context."
show_layout_line (doc): "The origin of the glyphs (the left edge of the line) will be drawn at the current point of the cairo context."
So it is no longer necessary to query `layout.get_baseline()`.
`directory.monitor(...)` -> `directory.monitor_directory(...)`.
It is important to specify that the file to monitor is a directory because maybe the directory does not exist yet and remove events would not be monitored.
* Rename "Persistent" to "Persistent over restarts".
* If disabled, "Persistent over toggles" has priority over "Persistent over restarts" and "Drawing on the desktop".
Close issue #42.
* Group "transform" attributes.
* Round "transform" attribute values.
* Remove unused stroke attributes.
* Add an "eraser" class attribute to let user retrieve the element role.
* Pass Clutter color and Pango fontDescription objects to elements, not strings.
* Do not use the color format '#rrggbbaa' in svg since it is not supported in GNOME 3.24.
Array is more semantically appropriate.
For example 2 actions may have the same translations (error of a translator). With an object (or a map), only the second would be displayed, which is problematic to alert to the problem.
Additionally, handle the case where some GSettings keybinding values are empty.
* Let the user choose the directory.
* Rework of Files.Images.
* area.currentImage is now an ... image, not an index.
* Add 'switch-image-file-reverse' keybinding.
* Add image gicons (from thumbnails) in the submenu.
* Images are reset on drawing mode left or on images added from the clipboard.
* It is no longer required to clamp the setting value in area.js.
* Add a "range" property, completed with another 'step' property, to PixelSpinButton in order to directly initiate the lower and upper values of the adjustment from the relevant setting range.
* Not related: fix an inversion between Pango and Cairo in element.js.