Move CollectionMetadata into its own component.

[lindapaiste]

Just trying to break up components that are doing way too much.

Changes:

• Move the code from the _renderCollectionMetadata method of Collection to a new component CollectionMetadata.
• Move the existing ShareURL component to a separate file as it used by CollectionMetadata but not by Collection (anymore).
• Fix a console warning:

Warning: validateDOMNesting(...): <div> cannot appear as a descendant of <p>.
in div (created by ShareURL)

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123

[PiyushChandra17]

Nicely Done

[raclim]

This looks overall great to me! Thanks so much for working on this and sorry again for the delay!