Add script to process strace output from #390
Add licence
Handle pread64 syscall too for older 32 bit archs
Add handling for pwrite, fdatasync and fsync
configure.ac: Fix detection of fdatasync(), which appears to have
been broken practically forever - this means we've probably been
using fsync() instead, which probably isn't a big additional
overhead.
Support various strace options.

If -y was used, we don't need to track fd to filename mappings.

Parse extra information added by -r, -i, -t, -tt and/or -ttt, but
ignore it for now.

Add comment showing usage.