* Save pxos as zip files in disguise
* Load pxo files as zip
* Add a checkbox in save dialog to let users include the final blended images in the pxo or not
* Initial work of a color picker that is always visible
* Make the new color picker fully functional
* Minor UI fixes
* Change the UI a bit so the color picker buttons look like they used to
To save horizontal space
* Add sliders as a separate panel and rename some file names
* Move the left/right color buttons next to the hex text edit
* Add color picker sliders to the same panel as the rest of the color picker, as an expandable/collapsible area
* Change default layout
* Some minor UI improvements
* Remove guides from ColorPicker.tscn
* Reduce the lines of code that calculate the average color
* Make Pixelorama remember if the color picker is expanded and its color mode
* Update tallscreen.tres
* Update tallscreen.tres
* Pixelorama now also remembers the last used picker shape
* Add some extra comments in the code
* Fix typo
* Add some translation strings
* Basic logic for layer effects
* Add an FX button and the ability to add effects, no way to remove or change properties of effects yet
* Basic and ugly UI for adding and removing effects, no property changing yet
* Swap effects
* Fix preload shader paths
* Change parameters for layer effects
* Change gradient parameter in layer effect shaders, and other fixes
* Use CollapsibleContainers for the shader properties
* Set the correct gradient interpolation mode and color space in the UI
* Make effects of group layers apply to children
* Change `apply_fx` to `apply_effects`, formatting, some extra doc comments
* Apply effects to other canvases, when merging layers and when exporting
* Display humanized names of the shader unifrms
* Some UI improvements to the LayerEffectsSettings
* Add an Enabled button in the layer effects window, and change checkboxes to checkbuttons
* Change BaseLayer.apply_effects() to take a cel as a parameter instead
* Make layer effect buttons be affected by the modulate icon color
* Add option in the View menu whether layer effects are displayed in the canvas or not
* Rename `apply_effects()` to `display_effects()`
* Add translation strings
* Add nearest filter to the gradient map
* Don't change Main.tscn
* Fix more translations
* Change the default cursor shape of the generated UI elements of the layer effects
* Add undo/redo and effect application (apply effect destructively)
There are some errors due to the usage of anonymous lambda methods in undo/redo, but it seems to be working well regardless.
* Make layer effect application work on all cels
