Thoughts about ax_resip.m4, anyone?

[Peter Simons]

Hi guys,

in https://savannah.nongnu.org/patch/index.php?6983, a friendly contributor
submitted a new macro: AX_RESIP. That macro is supposed to detect the libraries
from resiprocate.org.

My first-glance impression is that this macro doesn't offer much original
functionality, and also it's apparently still work in progress, but I might be
misjudging the situation.

How you feel about adding this macro to the archive?

Take care,
Peter