Clean up errored assets

[pereirinha]

Approach

• Adds means to clean up the sync error flag, allowing the assets to be retried to sync. This can be achieved by one of these:
  • Via the dashboard;
  • Via the Media Library;
  • Via the CLI commands

[tharsheblows]

There are two very small comments regarding capitalisation. If you think they don't matter then you can ignore!

I've tested all three scenarios also and they are working.

[pereirinha]

There are two very small comments regarding capitalisation. If you think they don't matter then you can ignore!

I've tested all three scenarios also and they are working.

Thank you @tharsheblows. I took care of these.