Also expose this in the native SDKs.

It's obsolete now, since config is handled in Redux. Also add a "defaultUrl"
prop so emdedding applications can select what the default base URL is.

The counterpart of the external API in the Jitsi Meet Web app uses the
search URL param jwt to heuristically detect that the Web app is very
likely embedded (as an iframe) and, consequently, needs to forcefully
enable itself. It was looking at whether there was a JSON Web Token
(JWT) but that logic got broken when the JWT support was rewritten
because the check started happening before the search URL param jwt was
parsed.

There were getDomain, setDomain, SET_DOMAIN, setRoomURL, SET_ROOM_URL
which together were repeating one and the same information and in the
case of the 'room URL' abstraction was not 100% accurate because it
would exist even when there was no room. Replace them all with a
'location URL' abstraction which exists with or without a room.

Then the 'room URL' abstraction was not used in (mobile) feature
share-room. Use the 'location URL' there now.

Finally, removes source code duplication in supporting the Web
application context root.

* fix(react/participant): store display name in redux

* feat(remotecontrol): Add option to display the authorization dialog in meet

* feat(remotecontrol): Enable ESLint and Flow

Adds translate function with default namespaces and options.

On RN we don't use the global APP object, so don't save the store there unless
it's defined, which is the case in the current web version. Also, check for
undefined explicitly, since a "if (!APP)" check will throw a ReferenceError.

The mobile app remembers the domain which hosted the last conference. If
the user specified a full URL first and specified a room name only the
second time, it was not obvious that the second conference would be
hosted on the domain of the first conference.

The files react/index.native.js and react/index.web.js ended up having
very similar source code related to initializing the Redux store. Remove
the duplication.

Additionally, I always wanted the App React Component to be consumed
without the need to provide a Redux store to it.

A bug was discovered in d17cc9fa which would raise a failure to push
into the browser's history if a base href was defined. Fix the failure
by removing react-router. Anyway, the usage of react-router was
incorrect because the app must hit the server infrastructure when it
enters a room because the server will choose the very app version then.

As an intermediate step on the path to merging jitsi-meet and
jitsi-meet-react, import the whole source code of jitsi-meet-react as it
stands at
2f23d98424
i.e. the lastest master at the time of this import. No modifications are
applied to the imported source code in order to preserve a complete
snapshot of it in the repository of jitsi-meet and, thus, facilitate
comparison later on. Consequently, the source code of jitsi-meet and/or
jitsi-meet-react may not work. For example, jitsi-meet's jshint may be
unable to parse jitsi-meet-react's source code.