Small refactoring of Mirador configuration

[davide-negretti]

Description

This is a small refactoring of the Mirador configuration file

Before:

(Mirador.viewer(
    {
      // settings
    },
    [
      // list of plugins
    ]
  )
)(manifest);

After:

const miradorConfiguration = {
  // settings
}

const miradorPlugins = [
  // list of plugins
];

Mirador.viewer(miradorConfiguration, miradorPlugins);

This refactoring is useful in situations where the developer wants to make some settings or some plugins depend on a configuration variable

Note that manifest object was already provided as the data property of the settings object

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