push profiling down deeper into rhizome_fetch_poll()'s children.
print a back trace whenever any signal is received.
Improve debug logging

- add debug.trace to help track down segfaults
- warn about alarms without names (which are then hard to track down).
Add lots of profiling to assist in debugging

- made some debug output conditional.
- make it possible to debug slip decoding without getting swamped by other output.
- Improve reporting of unnamed schedule() calls.
- always collect performance statistics, and report on any excess
  use (>1sec in every 3), even if debug.timing is not enabled.
- include file size information in Rhizome transfer messages.
- reduce output when debug.rhizome_rx is set.
improve reporting of broken manifests, and make conditional on
debug.rejecteddata
added facility to log a clue for crash handler to hint where things
got stuck/caused a crash.
fix segfault bug in slip decoding.
fixed two actual bugs in upper7_decode()
reformat /rssi web page to better fit on phone screens.
make rhizome transfer timeouts consistent.
always show sign when displaying link budget.
improve rhizome mdp re-request timeout handling so that it doesn't
do amazingly bad things on low-bandwidth packet radio links.
Create files for large rhizome bundles

- configurable size threashold
increase size for unix domain socket pathname from arbitrary 100
to PATH_MAX to solve tests erroring out on OSX with long temporary
file names.
created tool for automatically finding IN()s without matching
OUT()s or where return() is used instead of RETURN().
Added OUT() to end of all functions using IN() that lacked it to
make it easier to statically analyse this invariant.
Fixed several return instead of RETURNs detected through use of
this tool. #49
adjust a few function exits that were ending with OUT() to
call return last to avoid compiler warnings, but still pass
check-in-out-return consistency checks.
improved check-in-out-return.c to detect more subtle class of
IN() without OUT() (where OUT() is only conditionally executed).
fixed outstanding IN()/OUT() bugs identified by that.
Added config.debug.profiling to help locate such errors.
fix behaviour when rhizome http service is disabled so that
rhizomeprotocol test 3 can detect when rhizome http is disabled,
even though the http server itself runs for providing informational
services.
make return codes of "servald stop" discriminate between different
failure modes (makes it easier to debug some test failures)
removed temporary verbose output from test.