Add semantic type to resource

[gra-moore]

The streaming API but many other contexts it is valuable for a resource json fragment to clearly indicate what kind of thing it is.

Proposal:

add a new property to resource called: icarType whose value is a URI.
define a list of URIs for all existing ICAR types.

The property is optional.
For the purposes of the protocol this property would need to be present.

This change is backwards compatible.

[gra-moore]

proposed icarResourceType

[gra-moore]

proposed resourceType

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[cookeac]

Resolved by #279

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.