Improve the logs and error reporting functionality

[Xayton]

In order to help users having problems with the Arduino Agent, it's important to collect good error reports and make it easy for users to report them to the developers. This is a list of improvements linked to this goal:

• Crash report functionality should be enabled by default and log all the messages of the application
• Add a way to automatically delete logs when they get older than X days or use more space than a given limit
• Review the application logs
  • Check that the correct log level and messages are used throughout the application
  • Disable the GIN logging at startup
• When the port binding fails because it's already in use, improve the log and check if there is already a version of the agent running, so that the log can say that (the check can be done by calling a known Agent endpoint, or add a new "version" endpoint for this specific reason). This can also be used to implement a way to detect existing Agent instances and avoid multiple running agents.
• Improve the discoverability of the error reporting functionalities, by updating the menus:
  • create a new menu item "Error reporting" or "Debugging"
  • Move the "Open Debug Console" inside it
  • Move the "Remove crash reports" inside of it and rename it "Clear application logs"
  • Add a new item "Get application logs Zip" to compress the logs into a zip file that will be saved in the user's home and opened in the default OS file viewer (like it's done with the configuration file)
  • Add a "Restart agent" item, to make it easy to restart the agent.
• Document the application folders:
  • the application folder, where the executable is stored
  • the configuration folder
  • the .arduino-create folder, where downloadable data and logs are stored

While working on these improvements, also check these existing tasks:

• Too much log spam #194
• Multiple agent instances running on kill / restart #253
• Opening Create Agent twice creates two new instances #725