update freemarker to 2.3.18
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Key: SLING-2102
URL: https://issues.apache.org/jira/browse/SLING-2102
Project: Sling
Issue Type: Task
Components: Scripting
Reporter: Justin Edelson
Assignee: Justin Edelson-- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira
