NGM_BINARY2ASCII, which convert control messages to ASCII and back.
This allows control messages to be sent and received in ASCII form
using ngctl(8), which makes ngctl a lot more useful.
This also allows all the type-specific debugging code in libnetgraph
to go away -- instead, we just ask the node itself to do the ASCII
translation for us.
Currently, all generic control messages are supported, as well as
messages associated with the following node types: async, cisco,
ksocket, and ppp.
See /usr/share/examples/netgraph/ngctl for an example of using this.
Also give ngctl(8) the ability to print out incoming data and
control messages at any time. Eventually nghook(8) may be subsumed.
Several other misc. bug fixes.
Reviewed by: julian
