Check for updates on startup

[fstasi]

As an Arduino user I would like to receive a notification when a new version is available, so that I can decide wether to update my IDE (confirm) or defer to a later time

Acceptance Criteria:

1. • Scenario: IDE2.0 Usage (the IDE2 is already open or just opened)
   • Given that I’m using an outdated version of the IDE2 - When I do my work on the IDE - Then I expect an info message (i.e. toast, not invasive) that informs me that an update is available and the only action required to update, is to click on the button “Update“
2. • Scenario: IDE2.0 Usage (the IDE2 is already open or just opened)
   • Given that I’m using an outdated version of the IDE2 - When I click on the “update” button - Then I expect the IDE to download the correct artifact from downloads servers, stop the IDE2, and restart it maintaining the workspace pre-update
3. • Scenario: IDE2.0 Usage after the update
   • Given that I requested the IDE2 update - When I click on all the Icon and launchers I configured on my system - Then I expect the last IDE to be started together with all the related bundled updated software (use the CLI, fw-uploader, etc embedded in the latest release) without any disruption (meaning that a whole artefact replace is needed when the user choses to update)

tech considerations:

• being the IDE2.0 a bundle of various artifacts (see AC#3) we cannot use the electron-builder update functionality, but we need to download the whole Arduino IDE release artifact and replace the whole app
• the replacement process must be carefully designed to be supported on all the supported OSes (looking at you MacOs)