[reSIProcate] update on stdint changes

[Daniel Pocock <daniel@xxxxxxxxxxxxx>]

The Windows build appears to be fixed, but Scott has found that some of
the stdint changes were troublesome when building reCon on Windows, due
to similar stdint stuff in sipXtapi

I've moved the controversial part of the change to a branch:

https://svn.resiprocate.org/rep/resiprocate/branches/b-stdint-phase1

The other simplifications and unrelated fixes are still in main.

If the sipXtapi problems eventually have a simple solution then it would
be good to have this code finally merged before v1.9, but it is possible
that it will have to wait.