Revert naming of dwl IPC protocol to support other bars

[Frewacom]

dwl-guile has integrated the IPC patch in dwl, but using a different name (since it also extends the protocol). However, this means that other bars that make use of this protocol does not work under dwl-guile.

The solution is to split the current custom protocol into two, one for the general information (layout, tags, etc), and one for the dwl-guile specific methods.

[Frewacom]

Consider using the https://github.com/djpohly/dwl/wiki/ipc patch, instead of raphi's patch? Need to wait and see which protocol external bars will use.