MEDIUM: mux-h1: implement basic glitches support

MEDIUM: mux-h1: implement basic glitches support

We now count glitches for each parsing error, including those that
have been accepted via accept-unsafe-violations-*. Front and back
are considered and the connection gets killed on error once if the
threshold is reached or passed and the CPU usage is beyond the
configured limit (0 by default). This was tested with:

   curl -ivH "host : blah" 0:4445{,,,,,,,,,}

which sends 10 requests to a configuration having a threshold of 5.
The global keywords are named similarly to H2 and quic:

     tune.h1.be.glitches-threshold xxxx
     tune.h1.fe.glitches-threshold xxxx

The glitches count of each connection is also reported when non-null
in the connection dumps (e.g. "show fd").