Directory in opt should only be created if is true

Directory in opt should only be created if the boolean
$install_from_source is true.

Validate and manage boolean for install_from_source var and make the test succeed

Update README.md and instance.pp in order to reflect new behaviour on
Merge pull request #52 from krionux/master

Directory in opt should only be created if  is true
Don't add extra connectors for the same protocol unless specified.
Merge branch 'connector-port-fix' of github.com:philipwigg/puppetlabs-tomcat into connector-port-fix