fix cell alignment by a few pixels

IPython/frontend/html/notebook/static/notebook/less/cell.less

@@ -12,7 +12,7 div.cell {
     width: 100%;
     padding: 5px 5px 5px 0px;
     /* This acts as a spacer between cells, that is outside the border */
-    margin: 2px 0px 2px 0px;
+    margin: 2px 0px 2px 6px;
     outline: none;
 }
 

IPython/frontend/html/notebook/static/style/style.min.css

@@ -1426,7 +1426,7 input.engine_num_input{height:20px;margin-bottom:2px;padding-top:0;padding-botto
 .ansigrey{color:grey;}
 .ansibold{font-weight:bold;}
 .cell{border:1px solid transparent;display:-webkit-box;-webkit-box-orient:vertical;-webkit-box-align:stretch;display:-moz-box;-moz-box-orient:vertical;-moz-box-align:stretch;display:box;box-orient:vertical;box-align:stretch;width:100%;}.cell.selected{border-radius:4px;border:thin #ababab solid;}
-div.cell{width:100%;padding:5px 5px 5px 0px;margin:2px 0px 2px 0px;outline:none;}
+div.cell{width:100%;padding:5px 5px 5px 0px;margin:2px 0px 2px 6px;outline:none;}
 div.prompt{width:11ex;padding:0.4em;margin:0px;font-family:monospace;text-align:right;line-height:1.231em;}
 .celltoolbar{border:thin solid #CFCFCF;border-bottom:none;background:#EEE;border-top-right-radius:3px;border-top-left-radius:3px;width:100%;-webkit-box-pack:end;height:22px;}
 .no_input_radius{border-top-right-radius:0px;border-top-left-radius:0px;}