Added Lots of Documentation

Added some nice to haves
Improved and Unified General Code Layout

MathKit/MPExpressionLayout.h

@@ -9,14 +9,53 @@
 #import "MPLayout.h"
 
 
+/*!
+ @header
+ This file contains the <code>MPExpressionLayout</code> class.
+ */
+
+
 
 @class MPExpressionLayout, MPExpression, MPFunctionLayout;
 
+
+/*!
+    @class      MPExpressionLayout
+    @abstract   An expression layout draws an <code>@link
+                //apple_ref/occ/cl/MPExpression@/link</code>.
+ 
+    @discussion For more information on the layout system see the documentation
+                on the <code>@link //apple_ref/occ/cl/MPLayout@/link</code>
+                class.
+ */
 @interface MPExpressionLayout : MPLayout
 
+/*!
+    @method     initWithExpression:parent:
+    @abstract   Initializes an expression layout with the specified expression
+                and parent layout.
+ 
+    @discussion To initialize a layout for the root expression of an expression
+                tree specify <code>nil</code> as the <code>parent</code>.
+ 
+    @param      expression
+                The expression that sould be represented by the receiver. Must
+                not be <code>ni</code>.
+ 
+    @param      parent
+                The parent layout of the receiver. Specify <code>nil</code> to
+                initalize a root expression layout.
+ 
+    @return     A newly initialized expression layout.
+ */
 - (instancetype)initWithExpression:(MPExpression *)expression
                             parent:(MPFunctionLayout *)parent;
 
+
+/*!
+    @property   expression
+    @abstract   The expression represented by the receiver.
+ */
 @property (readonly, nonatomic, weak) MPExpression *expression;
 
 @end