Refine Site Domain conflict report & add support for SXA site linking

[AdamNaj]

Problems found with the report:

• when a site did not define hostName report was not listing it, when in fact Sitecore treated it as *
• when a site collided on a partially-wildcard-defined domain - this collision might not have been caught

"Open" action script goes to a site home page, but...
Improvement:

• When a site is an SXA site - it will be detected and the "Open" button will instead go to the site definition item. The previous implementation worked with Zen Garden templates.

[AdamNaj]

Implemented.