What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Documentation
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes. Issue #___
• No

The PR fulfills these requirements:

• When resolving a specific issue, it's referenced in the PR's title (e.g. fix: #xxx[,#xxx], where "xxx" is the issue number)
• A change file is added if any packages will require a version bump due to this PR per the instructions in the readme.

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

Other information:

Todo

• Add new event TrayEvent to track left, right and double click on tray icon (macOS, Windows, Linux).
• Add show_menu() hide_menu() to Window
• Move NativeImage behind a PlatformExt
• WIndows MenuItem variants similar to what we've done with Linux
• Send coords (bounds) of the tray icon if possible within TrayEvent If possible (macOS, Windows, Linux)
• Only forward WM_COMMAND messages that corresponds to a menu item as MenuEvent on windows
• Big cleanup
• Add showContextMenu(menu) to tray -- will do in another release as macOS seems complicated
• set_icon for Windows, Linux and macOS (custom image) -- could be done in another release

from @amrbashir

gtk c++ docs says there is GtkImageMenuItem but it is deprecated so gtk-rs doesn't have that

Fix #20
Fix #47
Fix #63
Fix #64
Fix #66
Fix #67