Improved exceptions

Many exceptions got an improvement due to changed class or description or details it is providing.
Is not complete, needs to be done in patches in the regions, where it is needed, since some are just
swallowed.

Removed total usage of pure RuntimeExceptions to 0.

src/main/java/appeng/server/AECommand.java

@@ -27,10 +27,9 @@ import net.minecraft.server.MinecraftServer;
 import com.google.common.base.Joiner;
 
 
-public class AECommand extends CommandBase
+public final class AECommand extends CommandBase
 {
-
-	final MinecraftServer srv;
+	private final MinecraftServer srv;
 
 	public AECommand( MinecraftServer server )
 	{