Extend ArrowheadService to use other core module

[BlackRose01]

Hello,

please extend the injection class "ArrowheadService" to use the other core modules, e.g. system registry or event handler.

KR,
BlackRose01

[borditamas]

Hello,

for event handler we have subscribeToEventHandler(..) and unsubscribeFromEventHandler(...), but yes we still owe with the other ones. I will do it soon.

BR, Tamás