Switch from tox.me to tox.chat in README.md
Switch from tox.me to tox.chat in README.md

Reason: https://blog.tox.chat/2015/07/current-situation-3/
dvor/Antidote,Antidote-for-Tox/Antidote,dvor/Antidote,wilfreddekok/Antidote,Antidote-for-Tox/Antidote,Antidote-for-Tox/Antidote,Antidote-for-Tox/Antidote,wilfreddekok/Antidote,dvor/Antidote,wilfreddekok/Antidote,wilfreddekok/Antidote,dvor/Antidote