Refactored toplevel code into match.py
Wrote fast (integration) test that doesn't need to download any data.
Fixed divide-by-zero vulnerablility in divergence()  geo.py
made spiderosm a package:  __init__.py
added match.py test.py and test_data/  (forgotten last commit)
moved top levels to examples subdir
cleaned up test_data/
all test output now goes to temp files (and is cleaned up even on
failure)
cleaned up testing
renamed examples/ bin/ and changed toplevel names to all begin with
'spider_'
README updated.
cleaned up comments
Updated README.txt