Add image upload support

Images can be uploaded, thumbnails are created, they're displayed within
the threads themselves. Just like four chans!

There is not an upload size limit set yet. Gotta get on that next.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

board/static/board/style.css

@@ -16,6 +16,24 @@ hr {
 
 /* Posts */
 /*.post_body { }*/
+.post_image_info {
+    font-size: small;
+    padding-bottom: 5px;
+}
+
+.post_image_thumbnail {
+    float: left;
+    padding-right: 5px;
+}
+
+/*
+Not sure if I like the in-line style or each post gets its own row style
+.post_content:after {
+    content: "";
+    display: table;
+    clear: both;
+}
+*/
 
 .post_id {
     cursor: pointer;