Zios Themes [r549]

Official forum thread link: https://forum.unity3d.com/threads/zios-editor-theme-support.411818/

[Changes]
• Significant performance improvements when entering/exiting play mode.
• Lazy loading of theme assets (after initial setup) for improved initial load times.
• Added Automatic palettes that use either 1 or 3 base colors for quick user customization.
• Added Obsidian and ObsidianB palettes at user's request.
• Refined Lavender, Leather, and Silversky palettes for better usability.
• Added support for fragment skinsets. These are used to allow grouping of guiStyles belonging to the same skin.
• Added support for theme variants. These are partial skinsets that rely on a base skinset.
• Added "Classy Forms" Simplicity variant which uses more defined buttons/controls.
• Added "Default Margins" Simplicity variant for using default unity margins (prevents play mode flicker in inspectors)
• Added "Windows Brushed" Simplicity variant as an alternative aesthetic.
• Added Copy/Paste support for Palettes/Fontsets via context menu.
• Added option to fully Disable System.
• Undo/Redo static class support (for Themes Preferences).
• Separated versions of theme system based on Unity version.
• Created sister GUISkin Editor project for easier maintenance of guiskin files.

[Installation]
• Delete all existing ZiosTheme dlls and Themes folders.
• Download zip based on your Unity version (based on the last number set)