Generate stack name on init

[akranga]

Today when user runs hubctl stack init then they will get initialised as the domain name has not been defined for the stack. There is possibility for stacks that doesn't have domain name at all this name will follow. To improve this situation, hubctl stack init should come up with random pet-name if it cannot derive from domain name

There are few cases we would like to address to make sure this is backwards compatible:

• [x] Stack has no parameters at all... In this case hub should generate random pet name and assign to both stack name and dns.domain (for backward compatibility again)
• [x] User defines dns.domain without a value. In this case: init command should go to bubbles-dns and fetch a new domain name with secret key and store it in .env file. Then stack name is a dns prefix
• [x] User defines dns.domain with specific value. In this case: init command should not go to bubbles-dns instead use the value provided by user. Stack name is the dns prefix
• [x] User defines stack name with the value but not defines dns.domain. In this case name of the stack must be for dns.domain (backwards compatibility)
• [x] User defines stack name but not assign a value. In this case: we generate a random pet-name and assign as both stack name and dns.domain
• [ ] Update documentation

[akranga]

@oginskis would you give it a try? There might be cases that have been missed

[oginskis]

Verified it when worked on TDSpora stacks. All known issues has been addressed. Closing