Add new terminal and close terminal icons

See #7732

src/vs/workbench/parts/terminal/electron-browser/media/close-inverse.svg

-<svg width="16" height="16" xmlns="http://www.w3.org/2000/svg"><title>Layer 1</title><rect height="3" width="11" y="7" x="3" fill="#C5C5C5"/></svg>
\ No newline at end of file
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 19.2.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<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"
+	 viewBox="0 0 16 16" style="enable-background:new 0 0 16 16;" xml:space="preserve">
+<style type="text/css">
+	.st0{fill:#C5C5C5;}
+</style>
+<path id="iconBg" class="st0" d="M6,12H5V6h1V12z M8,6H7v6h1V6z M10,6H9v6h1V6z M13,3v1h-1v10c0,0.6-0.4,1-1,1H4c-0.6,0-1-0.4-1-1V4
+	H2V3h3V2c0-0.6,0.4-1,1-1h3c0.6,0,1,0.4,1,1v1H13z M6,3h3V2H6V3z M11,4H4v10h7V4z"/>
+</svg>

src/vs/workbench/parts/terminal/electron-browser/media/close.svg

-<svg width="16" height="16" xmlns="http://www.w3.org/2000/svg"><title>Layer 1</title><rect height="3" width="11" y="7" x="3" fill="#424242"/></svg>
\ No newline at end of file
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 19.2.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<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"
+	 viewBox="0 0 16 16" style="enable-background:new 0 0 16 16;" xml:space="preserve">
+<style type="text/css">
+	.st0{fill:#424242;}
+</style>
+<path id="iconBg" class="st0" d="M6,12H5V6h1V12z M8,6H7v6h1V6z M10,6H9v6h1V6z M13,3v1h-1v10c0,0.6-0.4,1-1,1H4c-0.6,0-1-0.4-1-1V4
+	H2V3h3V2c0-0.6,0.4-1,1-1h3c0.6,0,1,0.4,1,1v1H13z M6,3h3V2H6V3z M11,4H4v10h7V4z"/>
+</svg>

src/vs/workbench/parts/terminal/electron-browser/media/new-inverse.svg

-<svg width="16" height="16" xmlns="http://www.w3.org/2000/svg"><title>Layer 1</title><rect height="11" width="3" y="3" x="7" fill="#C5C5C5"/><rect height="3" width="11" y="7" x="3" fill="#C5C5C5"/></svg>
\ No newline at end of file
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 19.2.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<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"
+	 viewBox="0 0 16 16" style="enable-background:new 0 0 16 16;" xml:space="preserve">
+<style type="text/css">
+	.st0{fill:#C5C5C5;}
+</style>
+<path class="st0" d="M15,8H9v6H8V8H2V7h6V1h1v6h6V8z"/>
+</svg>

src/vs/workbench/parts/terminal/electron-browser/media/new.svg

-<svg width="16" height="16" xmlns="http://www.w3.org/2000/svg"><title>Layer 1</title><rect height="11" width="3" y="3" x="7" fill="#424242"/><rect height="3" width="11" y="7" x="3" fill="#424242"/></svg>
\ No newline at end of file
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Generator: Adobe Illustrator 19.2.0, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<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"
+	 viewBox="0 0 16 16" style="enable-background:new 0 0 16 16;" xml:space="preserve">
+<style type="text/css">
+	.st0{fill:#424242;}
+</style>
+<path class="st0" d="M15,8H9v6H8V8H2V7h6V1h1v6h6V8z"/>
+</svg>