Support alizer default ports per framework

Which area/kind this issue is related to?

/area alizer /area documentation

Issue Description

This issue is part of the #1154 EPIC and focuses on the default_ports per framework we need to define. That said for each framework detector (e.g laravel_detector.go) we should define default ports. A good way could be to define a function GetDefaultPorts inside each detector:

func (d LaravelDetector) GetDefaultPorts() []string {
    return []int{8080}
}

If the user has included a flag --add-default-ports, if no port value is detected during port detection we can return those ports. Finally, additions to the existing documentation should be made.

Acceptance Criteria

[ ] A new flag --add-default-ports is created
[ ] Every detector should have defined default ports
[ ] Every detector should return default ports if --add-default-ports exists and no ports have been defined.
[ ] Test cases to ensure the above criteria
[ ] Update documentation (port detection especially) to mention this update.

devfile / api