Implemented Fallback Request

• [Added] You can now worry less about retry action action on failure, as it just do it for you. In order to guarantee a very high availability, we implemented recommended retry strategy for all API calls on all your read and write actions. (Currently, fallback request is not supported for insight.)
• [Added] AlgoliaSynonymsReference now easily set synonyms with just few lines of code

    // single
    algolia.index('contacts').synonyms.save(AlgoliaSynonyms(
      objectID: '1',
      type: SynonymsType.synonym,
      synonyms: ['iphne', 'iphone', 'ipone'],
      forwardToReplicas: true,
    ));
    
    // batch
    algolia.index('contacts').synonyms.batch([
      AlgoliaSynonyms(
        objectID: '1',
        type: SynonymsType.synonym,
        synonyms: ['iphne', 'iphone', 'ipone'],
        forwardToReplicas: true,
      ),
    ]);

• [Added] deleteObjects Delete by query: now you can delete objects based on your query.
• [Bug] addObject for add object without objectID has been fixed.
• [Bug] setData for set object data has been fixed Issue #52
• [Bug] partialUpdateObject for partial update object data has been fixed Issue #59

Full Changelog: 1.0.3...1.0.4