Added Lots of Documentation

Added some nice to haves
Improved and Unified General Code Layout

MathKit/MPSumFunctionLayout.m

@@ -9,14 +9,16 @@
 #import "MPSumFunctionLayout.h"
 
 #import "MPSumFunction.h"
-
 #import "NSIndexPath+MPAdditions.h"
 
+
 #define kSumFunctionStartExpressionOffset 0
 #define kSumFunctionTargetExpressionOffset 0
 #define kSumFunctionSumExpressionOffset 3
 #define kSumFunctionTrailingOffset 5
 
+
+
 @implementation MPSumFunctionLayout
 
 - (MPSumFunction *)sumFunction
@@ -24,16 +26,19 @@
     return (MPSumFunction *)self.function;
 }
 
+
 - (NSUInteger)indexOfLeadingChild
 {
     return 2;
 }
 
+
 - (NSUInteger)indexOfTrailingChild
 {
     return 2;
 }
 
+
 - (NSUInteger)indexOfChildAfterChildAtIndex:(NSUInteger)index
 {
     if (index != 2) {
@@ -42,21 +47,25 @@
     return [super indexOfChildAfterChildAtIndex:index];
 }
 
+
 - (NSUInteger)indexOfChildBelowChildAtIndex:(NSUInteger)index
 {
     return 0;
 }
 
+
 - (NSUInteger)indexOfChildAboveChildAtIndex:(NSUInteger)index
 {
     return 1;
 }
 
+
 - (NSIndexSet *)indexesOfRemainingChildren
 {
     return [NSIndexSet indexSetWithIndex:2];
 }
 
+
 - (CTLineRef)line
 {
     CTLineRef line = [self lineForPrivateCacheIndex:0 generator:^CTLineRef{
@@ -67,6 +76,7 @@
     return line;
 }
 
+
 - (NSRect)localLineBounds
 {
     NSRect lineBounds = CTLineGetBoundsWithOptions(self.line, 0);
@@ -77,6 +87,7 @@
     return NSMakeRect(xPosition, lineBounds.origin.y, lineBounds.size.width, lineBounds.size.height);
 }
 
+
 - (NSPoint)offsetOfChildLayoutAtIndex:(NSUInteger)index
 {
     NSRect childBounds = [self childLayoutAtIndex:index].bounds;
@@ -101,11 +112,13 @@
     return offset;
 }
 
+
 - (BOOL)childAtIndexUsesSmallSize:(NSUInteger)index
 {
     return (index == 0 || index == 1) ? YES : self.usesSmallSize;
 }
 
+
 - (NSIndexPath *)indexPathForLocalMousePoint:(NSPoint)point
 {
     if (point.x < CTLineGetBoundsWithOptions(self.line, 0).size.width / 2) {
@@ -115,6 +128,7 @@
     }
 }
 
+
 - (NSRect)generateBounds
 {
     NSRect lineBounds = CTLineGetBoundsWithOptions(self.line, 0);
@@ -139,6 +153,7 @@
     return bounds;
 }
 
+
 - (void)draw
 {
     // Get the current context