cleans up code to follow style guide

also removes notify's so unless something has actually changed during a
puppet run, this module wont cause reports to show up indicating changes
(in most cases, a puppet run should result in 0 changes, unless puppet
did something during that run, ie installed an application, reports that
are executing commands every run are not idempotent, and could cause
issues since puppet's default run interval is 30 minutes).

replaced exec creating the download path with a file resource instead,
this will not create nested directories, but in the calling profile of
this module could create them instead. Or the file download function
could be replaced by the staging module:
http://forge.puppetlabs.com/nanliu/staging

adds a source path variable, so people can use a general file bucket to
store their jdk installer, instead of putting it inside the modules
files directory (http://docs.puppetlabs.com/guides/file_serving.html)

this documents formatting has been updated to follow the style guide and
checked with the puppet-lint command to help make it conform to standard
puppet code. http://docs.puppetlabs.com/guides/style_guide.html and
http://puppet-lint.com/