Update commands provided to reload and check the status of videobridge.

* Prioritize messaging re: using hosted Jitsi if self-hosted is not required

* Update wording for self-hosting vs hosted

* Expand requirements sentence into document section

* Simplify Ubuntu universe step

* Condense repository and package installation steps

* Add comments for package installation steps

* Simplify wording around hostname configuration

* Simplify lets-encrypt wording

* Move certificate generation step before package installation

* Expand certificate instructions

* Move conference test step to post-installation

* Rephrase installation testing / confirmation step

* Extract platform-specific installation notes

* Rephrase superuser guidance

* Replace lists.jitsi.org link with web.archive.org pointer

* Place /etc/hosts example in code block

* Remove space before colon

* Add spacing before/after 'or' (improves github markdown rendering)

* Revert "Add spacing before/after 'or' (improves github markdown rendering)"

This reverts commit 9f33beb2ab.

* Nit: clarify apt/HTTPS relationship

* Revert "Expand requirements sentence into document section"

This reverts commit cf630983c0.

* Relocate Ubuntu universe repository advice

* More concise Ubuntu universe messaging

* Revert "Extract platform-specific installation notes"

This reverts commit 7161a700cb.

* Revert "Expand certificate instructions"

This reverts commit 5c479e7ffb.

* Revert "Move conference test step to post-installation"

This reverts commit a0ee279b7c.

* Revert "Simplify wording around hostname configuration"

This reverts commit ceab0ab9cf.

* Revert "Revert "Simplify wording around hostname configuration""

This reverts commit a7127d03dc.

* Revert "Revert "Revert "Simplify wording around hostname configuration"""

This reverts commit 1e5413690e.

* Revert "Remove space before colon"

This reverts commit 35cae52722.

* Mark Let's Encrypt step as optional

* Mark Let's Encrypt step as recommended

* Clarify Jitsi repository-add heading

* Nit: remove superfluous newline

* Fixup: restore Let's Encrypt descriptive text from master branch

* Update supported Ubuntu version to 18.04 (LTS)

* Add Ubuntu release codename

* Update minimum supported Debian version to 9 (Stretch)

* Undo relocation of Let's Encrypt script instructions

* Add Jitsi Meet mobile app certificate requirement notice

* 'Note' formatting consistency

* Rephrase sudo language

* Completely removes jetty config and defaults to nginx.

* Force configuring nginx or apache.

* Fixes certs when upgrading from jetty.

* Fixes certs and restarts jvb.

* Turnserver config conflicts apache2.

* Multi-domain sed only for nginx.

* Updates docs removing jetty.

- removed paragraph about old Debian Wheezy, the link is broken, and Wheezy doesn't even get security updates anymore, so seems unlikely anyone would do a new install with it.
- clarified that Let's Encrypt script uses only the HTTP challenge.
- added links to a few things that newbies might want to look up (nginx, apache, jetty, SIP, FQDN, Let's Encrypt, etc.
- added some basic debugging starting points, based on my experience
- some minor grammatical tweaks
- other minor tweaks

fixes #5260 (#5279)

* Adds package that can configure using turnserver for jitsi-meet.

Activates http2 on the nginx host and uses the alpn send with the web requests to multiplex traffic to be served as web of proxied to the turn server.
It needs nginx at least v1.13.10.
Adds turncredentials module from Philipp Hancke, with small modification (all int values for hosts need to be strings/tostring()) in order to be able to use the module with prosody 0.11.

* Moves loading of stream after loading stream module (50-..).

* Leaves DISABLE_TCP_HARVESTER to be handled by jvb.

* Fixes comments.

* Properly detect first time coturn install and configure it.

* Handles upgrading from jetty serving web.

* Does not create jvb user if already exists.

* Fixes let's encrypt and adds turnserver handling.

* Enables use of turn server in config.js if available.

* Adds a check whether prosody config exists.

There are cases where deployments can still have configured prosody in the main prosody config in /etc/prosody.

Fixes too many open files.

Recent Ubuntus come with only main repositories enabled. See #3427.

Tweaks for clarity.

Add potential additional package to install, tested on fresh Debian 9 installation.

The package jitsi-meet-prosody was missing from the list of packages.

Adds 'jicofo' package to Deinstall section.