Updated dataset editor

[maaikelimper]

this PR merges various updates for the dataset-editor:

• add license link
• add option to publish metadata with URLs only (no WIS2 data-notifications)

[amilan17]

Change

to "Create metadata without WIS2 data notifications"

[amilan17]

when an an end data is entered, I can still select "Data is ongoing"

[maaikelimper]

Proposal:
move checkbox at "initial information" pop-up to just before to sub-discipline topics selection -> use will need to select "other" to publish static metadata

[maaikelimper]

"Link URL" -> "URL"
"Link description" -> "Description"
"Link Type" -> "Type"

// link types for dataset links
        const linkTypeList = [
            { rel: 'archives', description: 'Online archive' },
            { rel: 'service-desc', description: 'API or Web Service' }
        ];

[maaikelimper]

@tomkralidis I've implemented some of the changes you requested:

This PR is available at http://136.156.129.229/wis2box-webapp/dataset_editor for testing