Added code for SIP custom event handler
Generified collections
Merge branch 'develop' into feature/Events
Merge branch 'develop' into feature/Events
Added dependencies of sponge to gradle
Worked on Multiblocks

*Separated API and implementations
*Moved API files to api package
*Implementations now use the sponge API instead of psuedo-code/no-code
*Javadocs on API files
Finished some Core initializing stuff
Worked on event handling

*Removed Initialization event
*Restructured code ( Moved API files to api package )
*Renamed SIPListenerPriority -> Priority
*Changed Event from class to interface
Merge branch 'feature/Multiblocks' into develop

Conflicts:
	SIPCore/src/main/java/org/sipplugin/core/SipCore.java
Moved ticking package to API root
Merge branch 'feature/Multiblocks' into develop
Cleaned up multiblocks code structure and added events

*Removed multiblock packaged and move stuff to ticking root
*Properly added @Override annotations to methods
*Formatted code
Deleted self implemented event system

Using the Sponge event system seems more robust and reliable than implementing our own system.
We can also extend sponge events anytime to make it easier to code
Merge branch 'develop' into feature/Multiblocks

Conflicts:
	SIPCore/src/main/java/org/sipplugin/core/event/SipEventManager.java