Fix link in UI text pointing to docs on application "Options" tab

The application "Options" tab has some text with a link to the documentation. The text is:

With aliasing enabled, users can have a different username (alias) for the "demo" application. This is useful if "demo" does not support user renaming. See the documentation.

The word "documentation" is currently linked to http://this.really.needs.to.go.somewhere.com.au/

Instead, please:

• Hook this link up to the help-paths.properties file, so that it supports our version control.
• Make it open in a new browser window/tab.
• Point the link to the following page: Specifying+a+User%27s+Aliases

(http://confluence.atlassian.com/display/CROWD/Specifying+a+User%27s+Aliases)