Some performance or memory optimizations

Replaced String concat in loops with StringBuilder (performance)
Replaced for with keySet + Map.get() through for with entrySet (perf)
Changed inner classes to static classes, mostly struct like (memory)

src/main/java/appeng/helpers/PatternHelper.java

@@ -41,7 +41,7 @@ public class PatternHelper implements ICraftingPatternDetails, Comparable<Patter
 	final boolean isCrafting;
 	public int priority = 0;
 
-	class TestLookup
+	static class TestLookup
 	{
 
 		final int slot;