Gallery and Tiled Gallery: Block settings should apply whether carousel is enabled or not

When adding a gallery block or tiled gallery block, clicking an image will always open the carousel no matter what block settings are selected. The block settings allow you to link to Attachment Page, Media File, or None, but these settings are not applied.

#### Steps to reproduce the issue

1. Add a new gallery block or tiled gallery block
2. Click on the block and then select one of the options under "Link to" in the block settings.
3. Publish the page

#### What I expected

The option selected in the block settings would apply.

#### What happened instead
Clicking any image in the gallery opens a carousel, even if the option Attachment Page, Media File, or None is selected.

Reported in 9770247-hc
Discussed this here: p1549297057187700-slack-triage

No files, tests, or entry points are named. Start by locating the Gallery and Tiled Gallery block implementations and reproduce the three "Link to" choices from the steps. Done means each selected option controls image clicks regardless of carousel settings, for both block types.

Written by the indexing model from the issue text.