Added Manifest for Listener

Added Manifest and Tests for Listener Element in server.xml. Updated the README and added an example for Tomcat 7 Instance with JMX Listener.
Added parent_server_port, fixed Attribute

Added Parameter parent_server_port to select the server element.
Allow Listener to be nested below Server, Engine, or Host elements
Clarify docs for tomcat::service

There was some confusion about whether or not this manifest would
provide an init script, so add a note in the README.
Merge pull request #63 from mhaskel/MODULES-1499

Clarify docs for tomcat::service
Merge pull request #1 from mhaskel/MODULES-1415

Allow Listener to be nested below Server, Engine, or Host elements
Merge pull request #57 from juame/MODULES-1415-ServerListener

Added Manifest for Listener
Update additional_attributes to support values with spaces

The value needs to be quoted so the augeas command works properly.
Exporting setenv.sh entries to make them operational
Rebase of #34 - export setenv entries

Make sure setenv entries have `export`, and update tests accordingly

Fixes puppetlabs/puppetlabs-tomcat#34
Merge pull request #64 from mhaskel/MODULES-1492

Update additional_attributes to support values with spaces
Merge pull request #65 from mhaskel/rebase_34

Rebase of #34 - export setenv entries