getCapability
@Nonnull
public <T> LazyOptional<T> getCapability(@Nonnull
                                                   Capability<T> capability,
                                                   @Nullable
                                                   Direction facing)
Retrieves the Optional handler for the capability requested on the specific side.
 The return value CAN be the same for multiple faces.
 Modders are encouraged to cache this value, using the listener capabilities of the Optional to
 be notified if the requested capability get lost.
- 定義:
- getCapabilityインタフェース内- ICapabilityProvider
- 戻り値:
- The requested an optional holding the requested capability.