add gist loading documentation

assets/css/browser-solidity.css

@@ -158,6 +158,15 @@ body {
     border-radius: 3px;
 }
 
+#header #optionViews .pre {
+    word-wrap: break-word;
+    background-color: #ccc;
+    font-family: monospace;
+    border-radius: 3px;
+    display: inline-block;
+    padding: 0 0.6em;
+}
+
 #header #optionViews .hide {
     display: none;
 }

index.html

@@ -96,7 +96,8 @@ THE SOFTWARE.
 					</div>
 				</div>
 				<div id="publishView">
-					<div class="row"><button id="gist" title="Publish all files as public gist on github.com"><i class="fa fa-github"></i> Publish Gist</button> Publish all open files to an anonymous github gist.</div>
+					<p><button id="gist" title="Publish all files as public gist on github.com"><i class="fa fa-github"></i> Publish Gist</button> Publish all open files to an anonymous github gist.</p>
+					<p>You can also load a gist by adding the following <span class="pre">#gist=GIST_ID</span> to your url, where GIST_ID is the id of the gist to load.</p>
 				</div>
 				<div id="envView">
 					<span id="executionContext">