Update brackets version to 1.13

Author: sobisht

index.html

@@ -121,7 +121,7 @@ <h1 class="brackets-logo">
             <h1><span data-i18n="index.page.hero.description">A modern, open source text editor that understands web design.</span></h1>
             <div id="download">
                 <a id="download-plain-brackets" class="large rounded radius button" href="#">
-					<div data-i18n="[html]index.page.hero.download">Download Brackets <d id="download-brackets-version">1.12</d></div>
+					<div data-i18n="[html]index.page.hero.download">Download Brackets <d id="download-brackets-version">1.13</d></div>
 				</a>
                 <div id="os-alert" class="alert-box radius" data-alert>
                 </div>