Composer replace islandora/openseadragon.

[rosiel]

GitHub Issue: Islandora/documentation#2270

• Other Relevant Links (Google Groups discussion, related pull requests,
  Release pull requests, etc.)

What does this Pull Request do?

Tells composer this package replaces islandora/openseadragon. Important when you're accessing the package as drupal/openseadragon.

• Related GitHub Issue: [CODE TASK] Update all modules to drupal/ namespace in Composer documentation#2270

• Other Relevant Links: (Google Groups discussion, related pull requests,
  Release pull requests, etc.)

What's new?

• Composer replace directive.

• Does this change add any new dependencies? no

• Does this change require any other modifications to be made to the repository
  (i.e. Regeneration activity, etc.)? no

• Could this change impact execution of existing code? no

How should this be tested?

Once merged, and tagged, and pulled by composer through Drupal's package repository, this will allow dependencies on islandora_mirador to know that this package satisfies the requirement.

Documentation Status

• Does this change existing behaviour that's currently documented? no
• Does this change require new pages or sections of documentation? no
• Who does this need to be documented for? email coming shortly.
• Associated documentation pull request(s): ___ or documentation issue ___

[rosiel]

This is breaking Packagist, as a package cannot replace itself.