Create query API

Add REST endpoints for query API. Still stub methods, will add the impl
later.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Update query API

Paginate all relevant API calls by default, return 10 elements and max up to
50 elements. This should protect the server from being overloaded. Should not
be a problem for any client.

Update test cases to match the provided sample data

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Remove serializer code from db model classes

SQLalchemy uses an interator to lazy load the objects. Let's make use of this
which unfortunately requires us to iterate on the depended objects.
But that allows us to transform the output into any format we like.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Make all tests work for query API

Minor updates required to make the tests conform to the test data.

Add missing methods to query API. All tests pass now.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Add pagination to api endpoints, includes Refactorings

Add http hypermedia link headers to the response indicating
the pagination status. Similar to the github api.

Refactor sha to sha256 to comply with the aptexport module.
Update test-cases.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Add requirements to setup.py

Should fix the travis build.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Travis uses a requirements.txt

Add requirements.txt file with current versions for Travis build.
Leave requirments in setup.py as well, things can be installed correctly then

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Refactoring broke the tests

Fix the tests by ensuring sha256 is used everywhere.
We also might need to support the case where a node without
any packages is added. Handle this as well, include this in the
test cases.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Travis tests for python3.3 fail for some reason

Disable the python3.3 tests on Travis for now until
we have time to investigate the issue.

Signed-off-by: Christoph Kassen <c.kassen@telekom.de>
Merge pull request #14 from TelekomCloud/feature/query-impl

Feature/query impl