Add DSpace identity service lookup
Add requirements file for python 2.6

importlib needs to be installed when running in a 2.6 environment.
Add 2.6 to travis testing scenarios
Rewrite summary to deal with nested data
Read and deal with 'success' property from DSpace
Updating for different DSpace response format
Adding cheap optimization on DSpace service call

The pipeline spends about 90% of its time on the DSpace service call.
This update caches the function call for each handle. It will have
almost no benefit when processing a small number of requests, but
should show significant improvement when processing a large volume of
requests.
Rewrite dates queries to avoid max doc size
Add summary data for handles
Add request buffer for batch mongo insert

I have no idea how big to make this buffer, but starting at 1000 seems
to work well enough. The memory footprint is negligable so it could
probably be increased quite a bit if need be.
Cache the parsed json data instead of the response

This puts requests's internal call to json.loads in the cached function
which speeds things up a bit. The downside is that requests resulting
in 500 errors will not be cached. However, these should be rare,
especially in production.
Cache the GeoIP lookup
Make summary script actually call handle summary
Add title to handle summary objects
Now make summary script really call handle summary

(I should really write a test for this)
Merge pull request #9 from gravesm/master

Finalizing pipeline behavior