Adding Maven badge to readme
Adding Maven badge to readme

navalev/azure-sdk-for-java,navalev/azure-sdk-for-java,selvasingh/azure-sdk-for-java,navalev/azure-sdk-for-java,selvasingh/azure-sdk-for-java,Azure/azure-sdk-for-java,Azure/azure-sdk-for-java,navalev/azure-sdk-for-java,selvasingh/azure-sdk-for-java,Azure/azure-sdk-for-java,Azure/azure-sdk-for-java,Azure/azure-sdk-for-java,navalev/azure-sdk-for-java