Label custom components in integration panel

[TheZoker]

The request

The new integration panel is really nice:

One thing I'm currently missing is, which integration is a custom component and which is loaded from core.
This would debugging things make easier in my opinion. (maybe someone forgot, that for testing purpose he placed a custom component - which overwrites a core integration - in his HA and since the last update it's causing issues).

The alternatives

Don't label custom components

Additional information

[balloob]

Another thing we should add is that if it's a custom integration, we should link to the documentation of the custom integration. Now all links go to our domain.

[alandtse]

@balloob Did you want a separate issue to cover the wrong link for custom integrations? I was about to open the issue but found your comment.

[frenck]

@alandtse There is already an issue open for that: #4929