Windows and Linux Tray Icon Fix

Copies the icons in the build process to make sure when can properly target it from the main electron process using path.resolve.

For Linux, the current default behavior will be to set close and minimize event to default (meaning it won't minimize to tray). This is because due to various Linux builds, the tray feature is going to be a hit or miss, and not having a visible tray means you won't be able to restore the window (https://electronjs.org/docs/api/tray).

For Windows and Mac, both should instantiate their respective icons and close/minimize accordingly.