title: mvvmcross Init method is not called if I inherit froma base ViewModel which is derived from MvxViewModel
body: <p>First I'm using <code>mvvmcross version 3.0.13</code>. When a class is inherited from a base class, which is inherited from <code>MvxViewModel</code>, the Init method won't be called from IoC. Current ugly workaround is to call the Init in the constructor. Could this be a bug or is there another pattern to use?</p>
  
  <p>In both classes (base and child of that base) it won't be called. For example:</p>
  
  <pre><code>public class BaseViewModel : MvxViewModel
  {
      protected CDataImportService DataImportService { get; private set; }
      protected CSettingService SettingService { get; private set; }
      protected CDataService DataService { get; private set; }
      protected CDocumentService DocumentService { get; private set; }
  
      public BaseViewModel(IDataService objDataService, IDataImportService objDataImportService, IDocumentService objDocumentService, ISettingService objSettingService)
      {
          DataImportService = (CDataImportService)objDataImportService;
          SettingService = (CSettingService)objSettingService;
          DataService = (CDataService)objDataService;
          DocumentService = (CDocumentService) objDocumentService;
      }
  
      public void Init()
      {
          Mvx.Trace("Init called in {0}", GetType().Name);
      }
  }
  
  public class DocumentsViewModel : BaseViewModel
  {
      public MenuViewModel(IDataService objDataService, IDataImportService objDataImportService, IDocumentService objDocumentService, ISettingService objSettingService)
          : base(objDataService, objDataImportService, objDocumentService, objSettingService)
      {
      }
  }
  </code></pre>