Use tables and css to create the diffstat graph, fix scaling

There was no need to use image-files for the graphs, so lets drop them.
At the same time, fix scaling of the graphs so that the full width is
used only if atleast 100 LOC are changed in one of the files.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

Makefile

@@ -60,7 +60,6 @@ install: all clean-cache
 	mkdir -p $(prefix)
 	install cgit $(prefix)/$(CGIT_SCRIPT_NAME)
 	install cgit.css $(prefix)/cgit.css
-	install add.png del.png $(prefix)/
 
 clean-cgit:
 	rm -f cgit *.o

cgit.css

@@ -284,9 +284,26 @@ table.diffstat td.graph {
 	vertical-align: center;
 }
 
-table.diffstat td.graph img {
+table.diffstat td.graph table {
 	border: none;
-	height: 8pt;
+}
+
+table.diffstat td.graph td {
+	padding: 0px;
+	border: 0px;
+	height: 7pt;
+}
+
+table.diffstat td.graph td.add {
+	background-color: #5c5;
+}
+
+table.diffstat td.graph td.rem {
+	background-color: #c55;
+}
+
+table.diffstat td.graph td.none {
+	background-color: none;
 }
 
 div.diffstat-summary {

ui-commit.c

@@ -29,7 +29,6 @@ void print_fileinfo(struct fileinfo *info)
 {
 	char *query, *query2;
 	char *class;
-	double width;
 
 	switch (info->status) {
 	case DIFF_STATUS_ADDED:
@@ -96,18 +95,15 @@ void print_fileinfo(struct fileinfo *info)
 	}
 	html("</td><td class='right'>");
 	htmlf("%d", info->added + info->removed);
-
 	html("</td><td class='graph'>");
-	width = (info->added + info->removed) * 100.0 / max_changes;
-	if (width < 0.1)
-		width = 0.1;
-	html_link_open(cgit_pageurl(cgit_query_repo, "diff", query),
-		       NULL, NULL);
-	htmlf("<img src='/cgit/add.png' style='width: %.1f%%;'/>",
-	      info->added * width / (info->added + info->removed));
-	htmlf("<img src='/cgit/del.png' style='width: %.1f%%;'/>",
-	      info->removed * width / (info->added + info->removed));
-	html("</a></td></tr>\n");
+	htmlf("<table width='%d%%'><tr>", (max_changes > 100 ? 100 : max_changes));
+	htmlf("<td class='add' style='width: %.1f%%;'/>",
+	      info->added * 100.0 / max_changes);
+	htmlf("<td class='rem' style='width: %.1f%%;'/>",
+	      info->removed * 100.0 / max_changes);
+	htmlf("<td class='none' style='width: %.1f%%;'/>",
+	      (max_changes - info->removed - info->added) * 100.0 / max_changes);
+	html("</tr></table></a></td></tr>\n");
 }
 
 void cgit_count_diff_lines(char *line, int len)