A search of the Advanced Search Guide for JIRA 6.4.x shows the function versionMatch() as native to JIRA's JQL functionality.

This is a known function that can be used with ScriptRunner and JQL Tricks, however, attempting to use this function in JIRA results in the following:

Unable to find JQL function 'versionMatch()' 

Please update the 6.4.x documents to reflect this is made possible via a third party plugin.