cygwin-crashreporter

A simple breakpad crashreporter for Cygwin.

By design, this is not a Cygwin application.  If there is a failure mode which
affects all Cygwin applications on a particular host, we still want to be able
to report the crash.

This can be invoked using Cygwin's error_start JIT facility. (e.g.
CYGWIN='"error_start=C:\cygwin\bin\cygwin-crashreporter-gui -r -k"')

Or, it could be invoked from a signal handler for SIGSEGV, SIGABORT etc.

Invoking the crashreporter like that isn't quite ideal as we don't capture the
EXCEPTION_POINTERS exception record into the minidump, so the minidump doesn't
record exactly which thread crashed, and with what exception.

This shortcomings could possibly be addressed with some changes to the Cygwin
DLL to give it a better way of invoking the crashreporter, passing that
information, but that's not happening today...
