Issue 205 ddo handling

[jamiehewitt15]

Fixes #205

Changes proposed in this PR:

• Ensuring that the right collection is used at all times, based on the version number in the ddo.
• Searching all schemas when retrieving, updating or deleting DDOs.
• Ensuring that we don't have the DDO in multiple collections at the same time.
• Creating new schema for short DDOs which are used for deprecated assets.

[paulo-ocean]

lgtm

[mariacarmina]

I have a question, looking at the code, I could not find the validation result when saving the DDO for metadata events (in the processor.ts). I think this issue should also include this part as well, not only at the database level, but correct me if I am wrong.

[jamiehewitt15]

I have a question, looking at the code, I could not find the validation result when saving the DDO for metadata events (in the processor.ts). I think this issue should also include this part as well, not only at the database level, but correct me if I am wrong.

The focus of this issue is making sure that we're using the right schema and collection when entering or retrieving data from the database. When the metadata is saved into a collection from src/components/Indexer/processor.ts it uses the update method on the ddoDatabase class. The update method has been adjusted within this PR to ensure that the right collection is used, based on the version number in the schema.

[jamiehewitt15]

Currently blocked by this issue as the short DDO can't pass the validation: #256

Could potentially implement a quick fix to bypass that issue:

1. Avoid doing any validation on the short DDO until the validation function has been updated
2. Add the extra missing fields back into the short DDO

[jamiehewitt15]

Tests are passing now as I implemented a workaround: avoiding doing any validation on the short DDO until the validation function has been updated

[mariacarmina]

lgtm