The Botserver uses section headers in the flaskbotrc to
determine which bot to run. Silently setting the section
headers to a bot's username is confusing and makes it
harder for Botserver users to figure out how to get the
Botserver to run the bots they want. This commit empties
all flaskbotrc section headers and thus makes the assignment
of bots explicit and mandatory.
Previously, the Botserver determined which bot to run for an
outgoing webhook by dispatching on a different URL endpoint
for each bot. Now, instead, the Botserver determines which bot
to run by the section header of the bot in the flaskbotrc.
This commit makes the frontend provide the new flaskbotrc
and updates the setup steps for the Botserver in the docs.