Add maximise and minimise icons

src/skins/vector/img/maximize.svg

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 15.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
+	 width="1792px" height="1792px" viewBox="0 0 1792 1792" enable-background="new 0 0 1792 1792" xml:space="preserve">
+<path fill="#76CFA6" d="M256,1408h1280V640H256V1408z M1792,288v1216c0,44-15.667,81.667-47,113s-69,47-113,47H160
+	c-44,0-81.667-15.667-113-47s-47-69-47-113V288c0-44,15.667-81.667,47-113s69-47,113-47h1472c44,0,81.667,15.667,113,47
+	S1792,244,1792,288z"/>
+</svg>

src/skins/vector/img/minimize.svg

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 15.0.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
+	 width="1792px" height="1792px" viewBox="0 0 1792 1792" enable-background="new 0 0 1792 1792" xml:space="preserve">
+<path fill="#76CFA6" d="M1792,1312v192c0,44-15.667,81.667-47,113s-69,47-113,47H160c-44,0-81.667-15.667-113-47s-47-69-47-113v-192
+	c0-44,15.667-81.667,47-113s69-47,113-47h1472c44,0,81.667,15.667,113,47S1792,1268,1792,1312z"/>
+</svg>