Deployment - App Server: tomcat/shared/classes/alfresco/extension/mimetype- add a custom-mimetype-map.xml file with the new MIME type definitions.
Deployment All-in-One SDK project:aio/platform-jar/src/main/resources/alfresco/module/platform-jar/mimetype-map-custom.xml - MIME Type definitions (note. the file name has to be this)