Some PHP Strict errors with itempropwp

Hi,
thanks for your plugin, i met somes php error, could you use query monitor to debug itempropwp.

call_user_func_array() expects parameter 1 to be a valid callback, non-static method itempropwp::init() should not be called statically
call_user_func_array() expects parameter 1 to be a valid callback, non-static method itempropwp_review::reviewinit() should not be called statically
call_user_func_array() expects parameter 1 to be a valid callback, non-static method sidebar_generator::init() should not be called statically

https://wordpress.org/plugins/itempropwp/