date attribute type support

[fgalan]

Formatting checking and storing it as ISODate() at MongoDB (in order to be used in attribute filters).

[fgalan]

The answer to following question in SOF has to be edited before closing this issue: http://stackoverflow.com/questions/32630801/query-orion-context-broker-by-dates

[fgalan]

Basic implementation in PR #1796. What is pending yet is support in q= filter, e.g.:

GET /v2/entitites?q<2016-04-05T14:00:00.00Z

[fgalan]

Finished in PR #1834

[fgalan]

QA Acceptance Test pending. Reopened and asigned to QATestPending milestone.

[iariasleon]

pending tests are created in its feature associated
bug associated: #1885

[iariasleon]

E2E covered in features/pepflows/022_pep2cbv2_datetimeprocessing.feature

[fgalan]

Issues in milestone QATestPendingE2ECovered are going to be closed (it is not realistic to think we would have people working on behave testing at the present moment). However, issue is labeled with QATestPending label in the case things change and we need to recover it.