contrib/cf-locate v2

@nickanderson this is similar to your script from #1040 with some changes:

* `-f` flag to turn full output (whole body or bundle) on; default is brief
* more efficient line-by-line processing
* no external `xargs` or `find` or `egrep` dependency (should work on Windows too)
* output format changed to:

```
-> body or bundle matching 'sync' found in ../../masterfiles/libraries/cfengine_stdlib.cf:1313
body copy_from sync_cp(from,server)
-> body or bundle matching 'sync' found in ../../masterfiles/lib/3.5/files.cf:953
body copy_from sync_cp(from,server)
-> body or bundle matching 'sync' found in ../../masterfiles/lib/3.6/files.cf:953
body copy_from sync_cp(from,server)
```

Please let me know if it looks OK and I'll make any necessary changes.