fixes bug 785430 - Add a service to add new products

@rhelmer r?

This basically just does what [the documentation](http://socorro.readthedocs.org/en/latest/installation/add-product-release.html) says to do except it makes it possible to kick this off from the middleware.

Once this has been done and you think it's good, I'll add it to the webapp and its admin UI. 
So one thing I'd suggest is not hardcoding the build ID, but generate it based on the current date - Socorro ignores a build ID older than 30 days.

I'd also suggest that the test should go a little further and actually check that the tables are populated as expected... let me play with this patch and I'll give you some concrete examples, in the form of a patch or PR)