Add ability to use native OS frame

[mahtaran]

Enables the functionality to use native OS frame controls. If there is a reason why these were disabled, feel free to close this.

Fixes #1030.

[OneEyeTurner]

So I went ahead and built all this out, and it works great!

The only thing that its missing is that this doesn't push the native frame to the pop out window of streams/video chats. That window still uses the original discord frame.

[mahtaran]

So I went ahead and built all this out, and it works great!

The only thing that its missing is that this doesn't push the native frame to the pop out window of streams/video chats. That window still uses the original discord frame.

Good catch @OneEyeTurner! Didn't think to check that. I just pushed some new changes which should make it so that any pop-out windows have the native frame if the option is turned on. It is done in a somewhat hacky fashion (never used Electron before) so if anyone knows a better solution, feel free to suggest changes.

@rauenzi Anything you'd like me to do before this can be merged?

Edit: I can already see one bug, when opening links it gives an error since it treats it as a pop-up. Will investigate…

[mahtaran]

Alrighty, it had to wait for a bit, but I believe it is now working perfectly! @rauenzi & @OneEyeTurner feel free to review.