Indenting MathJax rendered equations in rendered_html divs.

This is designed to match the indentation level of MathJax equations
in output.

IPython/html/static/notebook/less/renderedhtml.less

@@ -1,69 +1,74 b''
 .rendered_html{
 
     color: black;
     em {font-style: italic;}
     strong {font-weight: bold;}
     u {text-decoration: underline;}
     :link { text-decoration: underline }
     :visited { text-decoration: underline }
     h1 {font-size: 197%; margin: .65em 0; font-weight: bold;}
     h2 {font-size: 153.9%; margin: .75em 0; font-weight: bold;}
     h3 {font-size: 123.1%; margin: .85em 0; font-weight: bold;}
     h4 {font-size: 100%; margin: 0.95em 0; font-weight: bold;}
     h5 {font-size: 85%; margin: 1.5em 0; font-weight: bold;}
     h6 {font-size: 77%; margin: 1.65em 0; font-weight: bold;}
     ul {list-style:disc; margin: 1em 2em;}
     ul ul {list-style:square; margin: 0em 2em;}
     ul ul ul {list-style:circle; margin: 0em 2em;}
     ol {list-style:decimal; margin: 1em 2em;}
     ol ol {list-style:upper-alpha; margin: 0em 2em;}
     ol ol ol {list-style:lower-alpha; margin: 0em 2em;}
     ol ol ol ol {list-style:lower-roman; margin: 0em 2em;}
     /* any extras will just be numbers: */
     ol ol ol ol ol {list-style:decimal; margin: 0em 2em;}
 
     hr {
         color: black;
         background-color: black;
     }
 
     pre {
         margin: 1em 2em;
     }
 
 	pre, code {
 		border:				0;
 		background-color:	@bodyBackground;
 		color: 				@textColor;
 		font-size:			100%;
 		padding:			0px;
 	}
 
     blockquote {
         margin: 1em 2em;
     }
 
     table, tr, th, td {
         border: 1px solid black;
         border-collapse: collapse;
         margin: 1em 2em;
     }
 
     td,th {
         text-align: left;
         vertical-align: middle;
         padding: 4px;
     }
 
     th {
         font-weight: bold;
     }
 
     p {
         text-align: justify;
     }
 
     p + p {
         margin-top: 1em;
     }
+    
+    .MathJax_Display {
+        margin-left: 12ex;
+    }
+
 }