Co-authored-by: Lyubo Marinov <lmarinov@atlassian.com>
Co-authored-by: Paweł Domas <pawel.domas@jitsi.org>

This fix is based on storing the location URL object we are loading the
configuration for in the redux store. Once the config has been loaded (or it has
failed, for that matter!) we'll check if the current "config URL" is the same we
set, and discard the old one if they don't match.

Do not take legacy property into account if there's non-legacy value.

They will be stored in redux and the PageReloadOverlay will be displayed.

Note that this commit also introduces a subtle (and yet important!) change:
the location URL is now always set, regardless of the configuration loading or
not. This is needed in order for the retry logic to pick it up.

* doc: document disableH264 option

* [RN] Override disableH264 config option

We never want it disabled on mobile.

ESLint 4.8.0 discovers a lot of error related to formatting. While I
tried to fix as many of them as possible, a portion of them actually go
against our coding style. In such a case, I've disabled the indent rule
which effectively leaves it as it was before ESLint 4.8.0.

Additionally, remove jshint because it's becoming a nuisance with its
lack of understanding of ES2015+.

The global.performance.now polyfill is removed since it's polyfilled by
react-native-callstats.

navigator.product is read-only, so we don't run into the risk of it being
changed.

The config object defined by lib-jitsi-meet is not used by
lib-jitsi-meet only, jitsi-meet respects its values as well.
Moreover, jitsi-meet defined classes and/or functions which manipulate
that config object. Consequently, it makes sense to move the config
object and the associated classes and functions in a dedicated feature.