Disabling Headers in Azure Web Apps / Web Sites - or IIS for that matter
<configuration>
<system.webServer>
<security>
<requestFiltering removeServerHeader="true"/>
</security>
<httpProtocol>
<customHeaders>
<remove name="X-Powered-By" />
<remove name="X-Cache" />
</customHeaders>
</httpProtocol>
</system.webServer>
<system.web>
<httpRuntime enableVersionHeader="false"/>
</system.web>
</configuration>