Arlon CLI self-update

[cruizen]

The Arlon CLI needs to check for new versions and notify users to upgrade.
version check is handled separately.

Handle CLI upgrade : arlon update to upgrade.

Aha! Link: https://pf9.aha.io/features/ARLON-309

[Rohitrajak1807]

Replacing a running file can be a challenge. Apart from that, are we only upgrading to patches?

[cruizen]

Hey team! Please add your planning poker estimate with Zenhub @bcle @cruizen @jayanth-tjvrr @Rohitrajak1807 @ShaunakJoshi1407

[cruizen]

With update : we might want to update to a more recent major/ minor release sometimes (0.10.0 from 0.9.5)- or just update to the latest patch for currently installed release at times (e.g. 0.9.13 from 0.9.0)?

[cruizen]

@Rohitrajak1807 please look to your PR from v0.10 for the version check.

[Rohitrajak1807]

@Rohitrajak1807 please look to your PR from v0.10 for the version check.

I might even take the issue up. Let me do some exploration