Added custom server.xml configuration file

Adding a custom configuration file to customize tomcat deployment.
Added handlers to control tomcat

Startup, shutdown and restart handlers have been added for tomcat in
order to control its operation.
Added new task to overwrite old server.xml config

A task has been added to replace the existing server.xml config file
with a preset one.
Fixed an incorrect reference to webapps directory

The directory reference 'webapps' was spelled incorrectly. This has been
rectified, and should resolve some errors.
Fixed a minor error with destination of proxy

Destination directory was missing a trailing slash. This has been
readded.
Changed permissions to tomcat

Owner of the file has been changed to tomcat to increase security.
Removed a handler which stops tomcat

Handler to stop tomcat was unnecessary and therefore removed.
Removed unnecessary comments

Most of the verbose comments that were unnecessary have been removed for
a cleaner config file.
Removed unnecessary resources

Default database and its associated realms and listeners have been
removed as they are not needed.
Removed the webapps folder directory from url

Webapps directory does not need to be part of the url and has been
removed.
Implemented systemd integration for tomcat

Tomcat can now be controlled from systemd.
Transitioned over to service module

Service module is more purpose built for managing services, so it was
used instead of the shell module.
Transitioned handlers to service module.

Service module is better suited to managing services than the shell
module.
Merge pull request #17 from ausaccessfed/feature/tomcat-install

Setup tomcat to accept ajp connections from httpd

Fixes #15