feat: improved support for remote API

[lidel]

Closes #1586
Closes #1565
Closes #836
Closes #1194
Closes #1389
Closes #1031

This PR adds support for connecting to remote API that is protected by HTTP Basic Auth (#1586), enables entering custom configuration (a hidden feature for advanced users) and adds end-to-end tests.

Terse summary

• There is UI for changing the API address on the Settings screen
• Custom API address is stored in and read from window.localStorage[ipfsApi]
• ipfsApi is a string or a null
• If ipfsApi is null, ipfs-provider will try default address at /ip4/127.0.0.1/tcp/5001 (and same-origin for a good measure)
• ipfsApi can be a multiaddr, URL or JSON with config for ipfs-http-client used by webui
• User can enter URL with inlined basic auth user and password, we convert them to advanced config before passing to http client.
• E2E tests for using remote API with basic auth (URL or JSON, by setting localStorage[ipfsApi] or via Settings screen)
• Updated some dependencies related to E2E and made things bit more robust

Visual changes

Settings page

It is now possible to enter URL with inlined basic auth:

JSON with equivalent config for ipfs-http-client is also accepted:

Note: this is sort of an easter egg, we should not mention it in UI. This is mostly future-proofing. If someone has a very custom setup, webui will be able to support it without the need for a new release or a fancy UI for that one person.

Status page

Default state is the same(multiaddr), so most of the users will see no difference:

If a custom URL was entered on Settings, we also show URL on Status:

If JSON was entered, then we show it as-is. Here, a custom config with Basic Auth header:

I believe this is so niche, power user feature, that there is no point in making UI for this. Edit button is enough.
Instead of showing JSON, we could just print [JSON config] placeholder or something – @jessicaschilling thoughts?

[jessicaschilling]

@lidel LGTM -- thank you for the super-detailed screenshots 😊
Agree that just showing a message rather than the full JSON config is a good idea - plus reduces the risk of folks inadvertently sharing stuff in screenshots they don't want others to see.
How about Custom JSON configuration? (note no square brackets)

[lidel]

@jessicaschilling done:

One can test this even without basic auth setup, this JSON will work: {"url":"http://127.0.0.1:5001/api/v0"}

[lidel]

Passing config object to ipfs-http-client turned out tot be brittle and risky (eg. right now the object gets mutated and user sees different JSON than the one she entered).

I've addressed that in ipfs-shipyard/ipfs-provider#24 but need to update this PR to use documented parameters instead of url.
Probably safer to do it after some sleep, so will get back to this tomorrow 💤

[lidel]

Switched to ipfs-provider 1.1.0, which does not mutate the custom config, so the "undocumented url attribute" is no longer visible to the user. Only documented parameters for ipfs-http-client are used:

@rafaelramalho19 ready for your final review.