Fixed acf_get_value cache issue

https://github.com/AdvancedCustomFields/acf5-beta/issues/199#issuecomment-42736012
Signed-off-by: Elliot Condon <e@elliotcondon.com>
Fixed auto .json sub field bug

Signed-off-by: Elliot Condon <e@elliotcondon.com>
Merge branch 'master' of https://github.com/AdvancedCustomFields/acf5-beta