Default context for VC/VP to allow arbitrary JSON in credential subject

Closes #15

See merge request !15

Remove subject id from the VC

See merge request !14

Subject id must be represented in specific format, while currently
it's arbitrarily contructed from policy group/name/version
and causes problems with VC/VP signatures.

Verify proofs by calling the signer service

Closes #14

See merge request !13

Before this commit, the infohub was verifying VP proofs by itself.
Now this is delegated to the signer service for consistency, as the
signer service can act as both producer and verifier of proofs.

Expose prometheus metrics

Closes #12

See merge request !11

Replace LICENSE

See merge request !12

Add basic service documentation to README.md

Closes #4

See merge request !10

Resolve DID:WEB verification methods for proofs

Closes #11

See merge request !9

update

See merge request !8

update

See merge request !7

HTTP endpoint to import trusted data

Closes #7

See merge request !6

renamed old .gitlab-ci.yml and added new one

See merge request !5

Unit tests for infohub export functionality

Closes #8

See merge request !4

Use the signer service for adding VC and VP proofs

Closes #6

See merge request !3

The service doesn't use Vault client anymore as now
it asks the signer service for proofs.
Also golib is updated to the latest version.

HTTP endpoint for exporting policy evaluation results

Closes #3 and #5

See merge request !2

Initial service skeleton

Closes #2

See merge request !1