BLC-809 : When adding a MVEL compiled rule to the expressionCache, the result was being stored in a local variable.   This was causing the MVEL rules to not work on the very first execution of the rule.    This effected Page and StructuredContent rules.
Fix , also addresses a minor JavaDoc typo in PageDefaultRuleProcessor.
(cherry-picked from cdaf360)
(cherry-picked from c33e5fd)