Addition of an extension to CGcore v2

[olatunike]

IITA implemented CGcore v2 into her institutional data repository, CKAN. While integrating the repository with other research databases and tools, a challenge was encountered in the integration of MEL with CKAN metadata data schema. The CGcore v2 does not contain an extension for identifying project ID.
To address this, an extension was created with field label (Project ID) and CG core definition as "cg:project.identification_number"
The field is required to identify projects and the associated data from such project. CG core v2 was renamed as CG core v2.1 within the institution to identify the new extension created.

[alanorth]

Dear @olatunike, I think that's probably fine. We have a handful of those type of fields on CGSpace as well:

• cg.identifier.ccafsproject
• cg.identifier.ccafsprojectpii
• cg.identifier.ciatproject
• cg.identifier.iitatheme
• cg.identifier.wletheme

They were all created a few years ago. We know they are ugly and non standard but we had to store the project identifiers somewhere! Maybe we can migrate them to somewhere else appropriate in the future.