I don't think html escaping is needed, since pasties
go through the colorizer first.
I don't really like the workaround to not call on_send() when
I don't want the html output, it's a bit omg what's going on
there... I'll have to rewrite that bit.
IncRedis is now held by Response, if requested by the base class.
Response objects know their names, and they use it to load
the html (soon to be mustache) data from disk.
Main only prepares a factory, the factory then instantiates
the actual Response.
The code now correctly serves index.cgi when the request is /.
Remove kakoune's safe_ptr from inside src and put an updated
one in lib/kakoune.
