Remove the IRC notifications from Travis (we're not using IRC anymore), and the
stable/experimental badge from README.md (because they aren't being kept up to date).
Signed-off-by: Gergely Nagy <algernon@keyboard.io>
The default `onSetup` will call `.begin`, to support initializing plugins using
the V1 plugins while using `KALEIDOSCOPE_INIT_PLUGINS`. However, plugins that
implement a compatibility layer so that they can be used with both the new API,
and with `Kaleidoscope.use()` will have a `.begin` method too. Which the default
`onSetup` will call, and we'll register the compatibility layer too, in addition
to the new-style event handlers. This results in many things running twice,
which leads to all kinds of problems.
For this reason, override `onSetup`, so that it does not call `begin`. When used
with `Kaleidoscope.use()`, the plugin will still work, so compatibility is
maintained. But the bug is now gone.
Signed-off-by: Gergely Nagy <algernon@keyboard.io>