Rename uikit/CSSLayout to CSSLayoutKit.

Summary:
When trying to integrate this into an Xcode project that already included CSSLayout.[c|h], we were getting a linker error.

Upon digging in, I found out that Xcode was becoming confused because the imports of the uikit library and the c library are both `#import <CSSLayout/CSSLayout.h>`. So, it needed a new name.

Reviewed By: emilsjolander

Differential Revision: D4162621

fbshipit-source-id: b5f7624eb29f1b9eaebbed5104ec9ea8a12ad2e5

CSSLayoutKit/UIView+CSSLayout.h

@@ -0,0 +1,51 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#import <UIKit/UIKit.h>
+#import <CSSLayout/CSSLayout.h>
+
+@interface UIView (CSSLayout)
+
+- (void)css_setUsesFlexbox:(BOOL)enabled;
+- (BOOL)css_usesFlexbox;
+
+- (void)css_setDirection:(CSSDirection)direction;
+- (void)css_setFlexDirection:(CSSFlexDirection)flexDirection;
+- (void)css_setJustifyContent:(CSSJustify)justifyContent;
+- (void)css_setAlignContent:(CSSAlign)alignContent;
+- (void)css_setAlignItems:(CSSAlign)alignItems;
+- (void)css_setAlignSelf:(CSSAlign)alignSelf;
+- (void)css_setPositionType:(CSSPositionType)positionType;
+- (void)css_setFlexWrap:(CSSWrapType)flexWrap;
+
+- (void)css_setFlexGrow:(CGFloat)flexGrow;
+- (void)css_setFlexShrink:(CGFloat)flexShrink;
+- (void)css_setFlexBasis:(CGFloat)flexBasis;
+
+- (void)css_setPosition:(CGFloat)position forEdge:(CSSEdge)edge;
+- (void)css_setMargin:(CGFloat)margin forEdge:(CSSEdge)edge;
+- (void)css_setPadding:(CGFloat)padding forEdge:(CSSEdge)edge;
+
+- (void)css_setWidth:(CGFloat)width;
+- (void)css_setHeight:(CGFloat)height;
+- (void)css_setMinWidth:(CGFloat)minWidth;
+- (void)css_setMinHeight:(CGFloat)minHeight;
+- (void)css_setMaxWidth:(CGFloat)maxWidth;
+- (void)css_setMaxHeight:(CGFloat)maxHeight;
+
+// Get the resolved direction of this node. This won't be CSSDirectionInherit
+- (CSSDirection)css_resolvedDirection;
+
+//! @abstract Perform a layout calculation and update the frames of the views in the hierarchy with th results
+- (void)css_applyLayout;
+
+//! @abstract Compute the size of a layout with a constrained size.
+- (CGSize)css_sizeThatFits:(CGSize)constrainedSize;
+
+@end