Fix videoConferenceJoined and videoConferenceLeft event names

Adds the --host argument to the jicofo command, as suggested by exs on irc.

Now the web app can be installed separately from jicofo and jitsi-videobridge, or can be installed on machine running nginx or apache. Currently only nginx will be configured and apache config is left to user. Later we can add and the apache config. Renames jitsi-meet to jitsi-meet-web (just the web content) and jitsi-meet-web-config (configuring jetty, nginx or apache). A new jitsi-meet package will be introduced, a meta package depending on jicofo, jvb and the current packages.

As a step toward merging jitsi-meet-react with jitsi-meet to share as
much source code as possible between mobile and Web, merge the part of
jitsi-meet-react's source tree which supports mobile inside the
jitsi-meet source tree and leave jitsi-meet-react's Web support in the
source code revision history but don't have it in master anymore because
it's different from jitsi-meet's Web support. In other words, the two
projects are mechanically merged at the file level and don't really
share source code between mobile and Web.

There is no YOURSECRET4 mentions in the document

Add a note about the need to forward ports, as suggested by @joudinet on github.

Adds jicofo install instructions.

Adds 'jicofo' package to Deinstall section.