Speed up tomcat8 startup

1. Disable Servlet 3 scanning
Modify tomcat/conf/catalina.properties file

org.apache.catalina.startup.ContextConfig.jarsToSkip=*.jar
tomcat.util.scan.StandardJarScanFilter.jarsToSkip=*.jar


2. Modules start in parallel
Modify tomcat /conf/server.xml
add attributes
startStopThreads="0"

<Engine
  ..
  startStopThreads="0"
>
  <Host
    ..
    startStopThreads="0"
  > for each host and engine