adding host.json schema for logger, aggregator, and applicationInsights
adding host.json schema for logger, aggregator, and applicationInsights

Azure/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,Azure/azure-webjobs-sdk-script,Azure/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,fabiocav/azure-webjobs-sdk-script,Azure/azure-webjobs-sdk-script