1: Added capability for user to specify truststoreFile, truststorePass a...

Hi,

This aims to solve [issue #60][issue60] by introducing support for providing a trustStore and enabling clientAuth.

Hopefully the commit details and new tests are self explanatory but don't hesitate to ask if anything is unclear or if you feel anything further needs to be done in order to accept this pull request.

Cheers,

Edd

[issue60]: https://github.com/bmuschko/gradle-tomcat-plugin/issues/60