meteor + apache should carry warnings about websockets

[OnixGH]

The deployment walkthrough already warns about websockets, but there are more places where you can arrive via Google.

Since meteor relies heavily on websockets, maybe these sections should be emptied with a warning to use nginx or apache + reverse proxy altogether.

[mariohmol]

Just a reminder to warning apache2.4 because you need mod_wstunnel to make the reverse proxy with websockets, and that is supported just by 2.4.

Please update as well considering meteor with ionic2.