Refactors grid connections (#3219)

Extracted all checks and subsequent updates to a factory method from the constructor.
Reordered checks to check for nulls before anything else.
Also existing connections before security breaks.
Fixes TileController#checkController() using the wrong position.
Added debug logging for failed connections.
Improved logging.
Inversed boolean so false no longer means security check passed.
Only issue a security break on SecurityConnectionException.

src/main/java/appeng/parts/CableBusContainer.java

@@ -241,11 +241,11 @@ public class CableBusContainer extends CableBusStorage implements AEMultiTile, I
 								{
 									try
 									{
-										new GridConnection( cn, sn, AEPartLocation.INTERNAL );
+										GridConnection.create( cn, sn, AEPartLocation.INTERNAL );
 									}
 									catch( final FailedConnectionException e )
 									{
-										// ekk!
+										AELog.debug( e );
 
 										bp.removeFromWorld();
 										this.setCenter( null );
@@ -292,11 +292,11 @@ public class CableBusContainer extends CableBusStorage implements AEMultiTile, I
 						{
 							try
 							{
-								new GridConnection( cn, sn, AEPartLocation.INTERNAL );
+								GridConnection.create( cn, sn, AEPartLocation.INTERNAL );
 							}
 							catch( final FailedConnectionException e )
 							{
-								// ekk!
+								AELog.debug( e );
 
 								bp.removeFromWorld();
 								this.setSide( side, null );
@@ -637,6 +637,7 @@ public class CableBusContainer extends CableBusStorage implements AEMultiTile, I
 								catch( final FailedConnectionException e )
 								{
 									// ekk
+									AELog.debug( e );
 								}
 							}
 						}

src/main/java/appeng/parts/misc/PartToggleBus.java

@@ -41,6 +41,7 @@ import appeng.api.parts.IPartHost;
 import appeng.api.parts.IPartModel;
 import appeng.api.util.AECableType;
 import appeng.api.util.AEPartLocation;
+import appeng.core.AELog;
 import appeng.core.AppEng;
 import appeng.helpers.Reflected;
 import appeng.items.parts.PartModels;
@@ -208,6 +209,7 @@ public class PartToggleBus extends PartBasicState
 					catch( final FailedConnectionException e )
 					{
 						// :(
+						AELog.debug( e );
 					}
 				}
 				else

src/main/java/appeng/parts/p2p/PartP2PTunnelME.java

@@ -247,6 +247,8 @@ public class PartP2PTunnelME extends PartP2PTunnel<PartP2PTunnelME> implements I
 					{
 						final TileEntity start = this.getTile();
 						final TileEntity end = me.getTile();
+						
+						AELog.debug( e );
 
 						AELog.warn( "Failed to establish a ME P2P Tunnel between the tunnels at [x=%d, y=%d, z=%d] and [x=%d, y=%d, z=%d]",
 								start.getPos().getX(), start.getPos().getY(), start.getPos().getZ(), end.getPos().getX(), end.getPos().getY(),