Model Redesign: Added Reference Frames

Added Inverse Functions
UI Redesign
Cleaned Code

MathPad/MPFunctionLayout.m

@@ -14,6 +14,7 @@
 #import "MPSumFunctionLayout.h"
 #import "MPParenthesisFunction.h"
 #import "MPParenthesisFunctionLayout.h"
+#import "MPPowerFunctionLayout.h"
 
 #import "NSIndexPath+MPAdditions.h"
 
@@ -28,6 +29,8 @@
         return [[MPSumFunctionLayout alloc] initWithFunction:function parent:parent];
     } else if (class == [MPParenthesisFunction class]) {
         return [[MPParenthesisFunctionLayout alloc] initWithFunction:function parent:parent];
+    } else if (class == [MPPowerFunction class]) {
+        return [[MPPowerFunctionLayout alloc] initWithFunction:function parent:parent];
     }
     return [[self alloc] initWithFunction:function
                                    parent:parent];
@@ -101,6 +104,16 @@
     return [self indexPathForLocalMousePoint:point];
 }
 
+- (NSUInteger)indexOfLeadingChild
+{
+    return 0;
+}
+
+- (NSUInteger)indexOfTrailingChild
+{
+    return 0;
+}
+
 - (NSUInteger)indexOfChildBeforeChildAtIndex:(NSUInteger)index
 {
     return NSNotFound;