Managed gateway integration

[PavelJankoski]

Summary

Integration of managed gateway functionality.

Changes

• New menu item for managed gateway in the gateway details.
• Connection settings and wifi profiles screens.

Testing

Steps

1. Login to console.
2. Go to gateways screen.
3. Click on some managed gateway.
4. In the gateway details screen go to connection settings and wifi profiles screens.
5. Try all CRUD operations in those screens.

Results

Notes for Reviewers

The base branch will be changed to current master.

@kschiffer Please provide tooltip content and correct doc links

Checklist

• Scope: The referenced issue is addressed, there are no unrelated changes.
• Compatibility: The changes are backwards compatible with existing API, storage, configuration and CLI, according to the compatibility commitments in README.md for the chosen target branch.
• Documentation: Relevant documentation is added or updated.
• Testing: The steps/process to test this feature are clearly explained including testing for regressions.
• Infrastructure: If infrastructural changes (e.g., new RPC, configuration) are needed, a separate issue is created in the infrastructural repositories.
• Changelog: Significant features, behavior changes, deprecations and fixes are added to CHANGELOG.md.
• Commits: Commit messages follow guidelines in CONTRIBUTING.md, there are no fixup commits left.

[johanstokking]

Awesome, will test this as well.

You should be able to drop two of my commits in your trail, see the list here.

[johanstokking]

Can we hide the gcs.managed.* events from the event data view?

They are basically intended to render the Managed Gateway panel, not really as events. It's a bit weird they appear immediately when opening the gateway.

[johanstokking]

• Can you take the model from the managed gateway update message for the title, instead of "Managed gateway" ?
• Where does the image come from? Is that static?
• If I want to specify a WiFi profile just for this gateway, it still asks for a Profile Name. There should not be a Profile Name prompted, it should be a randomly generated one.

[johanstokking]

Ethernet is (typically) always enabled. The checkbox is more for customizing ethernet settings. Please update the checkbox label.

[PavelJankoski]

• Where does the image come from? Is that static?

@johanstokking Yes the image is static.

[johanstokking]

• Where does the image come from? Is that static?

@johanstokking Yes the image is static.

OK, it shouldn't be. Let's remove the image for now then.

[kschiffer]

Thanks for the hard work! From my manual testing, it appears quite thorough and the end-to-end test should reflect that as well. Also styling wise, it was quite on point, I've just added a small fix commit. 

Please see my comments. Most notably, error handling is somewhat stubbed still.