Fix 4326 mikemurray import me not

[mikemurray]

Resolves #4326
Impact: breaking
Type: bugfix

Issue

The Reaction importer tries to import data into various collections, even if data already exists. It tries to be smart about merging, but sometimes that results in unpredictable behavior. This will prevent the app from starting and is not easily recovered from.

Solution

• Collection.find().count() === 0 to wrap import statements in /server/startup/load-data.js
• Guard against errors in /server/api/core/importer.js in Importer.commit.

Breaking changes

• The Products, Shipping, and Tags collections will no longer have fixture data imported into if they have documents.
• Modifying Product.json, Shpping.json or Tags.json will have no effect after the first import. Data will need to be imported using the Reaction importer directly.

Testing

1. With a fresh app go to the PDP page as an admin
2. Change the product title on the PDP page. I did Basic Reaction Product--
3. Restart the app either with a code change or, stop/start
4. The app should start with no errors, and the Basic Reaction Product should not be modified.
5. Modify /private/data/Products.json and save.
6. Wait for the app to refresh
7. Observe that your changes have not been imported

[spencern]

Tested and reproduced error. This PR fixes. 👍