Warn when audio settings need to be reset

[neilenns]

Fixes #143

• Adds a new version property to the configuration
• Adds a new config class that manages everything relating to configs, including migration
• Add a method for migrating from v1 to v2 config, which clears the audio settings and updates the AlwaysOnTop property (refactored from a previous release)
• Adds a way to force the settings dialog to show from the main process
• Automatically show the settings dialog on first run (no saved settings) or audio settings reset (upgrade)
• Automatically select the Audio API if there's only one option and the user didn't have one selected already
• Force clear invalid config.json files. More on this below.
• Handle JSON parsing errors in the config by resetting to the default. More on this below.

Verified the following configurations work:

1. Fresh launch with no settings: no prompt, settings dialog, WASAPI auto-selected
2. Pre-beta settings, audio configured: prompt, settings dialog shows, WASAPI auto-selected
3. Beta settings, audio configured: no prompt, no settings dialog

Other notes

When testing I made an empty config.json file thinking that would just be an empty config, but it resulted in an unhandled JSON parsing exception in electron-store. Since the config file isn't meant to be hand-edited I added the option to new Store() to force clear the config if it's invalid instead of throwing an exception.

I also accidentally borked the JSON in a config file which lead to unhandled exceptions being thrown. Solved this by wrapping the parsing in a try/catch and reverting to default config if something went wrong.

[neilenns]

Ok, tested with useEffect and it seems to work.