articles:
https://www.juliensobczak.com/inspect/2016/08/28/spring-boot-from-scratch.html

reference:
https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto-configure-tomcat

catalina.properties
    common.loader
https://stackoverflow.com/questions/27268048/spring-boot-where-to-put-properties-files-when-deploying-to-tomcat

traditional deploy:
http://docs.spring.io/spring-boot/docs/current/reference/html/howto-traditional-deployment.html


http://docs.spring.io/autorepo/docs/spring-boot/current/api/org/springframework/boot/context/embedded/tomcat/TomcatEmbeddedServletContainerFactory.html
    addContextCustomizers

In case of embedded Tomcat with Spring-boot:
The class you can use to manipulate Tomcat settings is:
    EmbeddedServletContainerCustomizer

Through this you can add a TomcatContextCustomizer (addContextCustomizers)
http://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/context/embedded/tomcat/TomcatContextCustomizer.html

https://tomcat.apache.org/tomcat-8.0-doc/api/org/apache/catalina/Context.html
https://tomcat.apache.org/tomcat-8.0-doc/class-loader-howto.html


connectors:
https://www.mkyong.com/spring-boot/spring-boot-configure-maxswallowsize-in-embedded-tomcat/

loaders-tomcat-src:
https://stackoverflow.com/questions/6254869/order-of-tomcat-classloaders-common-shared-and-server