Upgrade to Tomcat v9.x

[sashakames]

We are getting flagged at LLNL for running Tomcat 8, so the clock is ticking....
I just upgraded to Tomcat v9.0.x the latest of that and seems to launch esg-search without a problem.
Still working on THREDDS

[sashakames]

#248 addresses this.

[sashakames]

Did we ever get this to work? LLNL site isn't running but old versions with CVEs will affect other sites.