feat(macos): add SystemTray::set_tooltip , ref #409

[pevers]

What kind of change does this PR introduce?

This implements the set_tool_tip method on a tray. I understand that this will probably not be merged before the v1 release. Please let me know if I can continue to work on this to also support the other platforms or if you would rather wait.

This should close #409

• Bugfix
• Feature
• Docs
• New Binding issue #___
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change?

• Yes, and the changes were approved in issue #___
• No

Checklist

• When resolving issues, they are referenced in the PR's title (e.g fix: remove a typo, closes #___, #___)
• A change file is added if any packages will require a version bump due to this PR per the instructions in the readme.
• I have added a convincing reason for adding this feature, if necessary

Other information

[pevers]

Hi, sorry to bother @wusyong , is it ok to continue work on this?

[amrbashir]

@pevers sorry for the delay. It would be perfect if you can finish Linux and Windows implementation but if you don't want too I can merge this and add them later.

[pevers]

@pevers sorry for the delay. It would be perfect if you can finish other Linux and Windows implementation but if you don't want too I can merge this and add them later.

Thanks for your reply @amrbashir ! I currently don't have access to my Windows machine, so I updated this PR and I can create an issue for the Windows and Linux implementation if that is OK?

[amrbashir]

It is fine, I will add them in this PR tomorrow or later today.

[amrbashir]

Sorry for the delay, I totally forgot I was going to implement other platforms.

It seems Linux's libappindicator doesn't support setting tooltips so I refactored the PR a bit for future Windows implementation because I can't do it right now.

[amrbashir]

Thanks