Create standalone components for each feature and move all state to them.
Toolbars are now dummy containers.

* ref: video muted state

Get rid of 'videoMuted' flag in conference.js

* ref: audio muted state

Get rid of 'audioMuted' flag in conference.js

* fix(conference.js|API): early audio/video muted updates

* ref(conference.js): rename isVideoMuted

Rename isVideoMuted to isLocalVideoMuted to be consistent with
isLocalAudioMuted.

* doc|style(conference.js): comments and space after if

* ref: move 'setTrackMuted' to functions

* fix(tracks/middleware): no-lonely-if

* ref(features/toolbox): get rid of last argument

* ref(defaultToolbarButtons): rename var

The functions need not return anything, or it will be dispatched as another
action.

toolbox/functions has functions that are specific only to web,
specifically defaultToolbarButtons. This has caused the native
build to attempt to bring in a web dependency which leads to a
build error. The fix for now is splitting web functions from
native functions to resolve the build error.