Conversion Reports: Add conversion reports to AppNexus RequestCampaignReportActivity
 * Add new AppNexusReportType enum input value "ReportType"
 * Add new scheduler registry for conversion reports
 * Schedule conversion reports at the end of campaign export along with the delivery reports
Conversion Reports: Retrieve conversion reports
 * Determine retrieved report raw data index association name and transform activity task by report type

TODO: Only schedule initial conversion report request if config says so
TODO: Dig report type out of the report AppNexus response (AppNexusApiClient.Reporting.cs)
TODO: Map AppNexus report object report type to AppNexusReportType (RetrieveCampaignReportActivity.RetrieveReport)
TODO: Implement activity for DynamicAllocationActivityTasks.GetCampaignConversionData
Merge branch 'master' into TSPixelReport
Merge branch 'master' into TSPixelReport
Conversion Reports: Handle retrieved conversion reports
 * Only schedule initial conversion report request if config says so
 * Dig report type out of the report AppNexus response (AppNexusApiClient.Reporting.cs)
 * Map AppNexus report object report type to AppNexusReportType (RetrieveCampaignReportActivity.RetrieveReport)
 * Implement stub DynamicAllocationActivityTasks.GetCampaignConversionDataActivity