ui-tree: link to plain view instead of blob view

The urls for plain view makes it possible to download blobs without knowing
their SHA1, but the function needs to be promoted and the link from tree
view seems like a perfect fit.

PS: Although hidden, the blob view still is nice for direct blob access so
there's no point in removing it.

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

ui-shared.c

@@ -243,6 +243,12 @@ void cgit_tree_link(char *name, char *title, char *class, char *head,
 	reporevlink("tree", name, title, class, head, rev, path);
 }
 
+void cgit_plain_link(char *name, char *title, char *class, char *head,
+		     char *rev, char *path)
+{
+	reporevlink("plain", name, title, class, head, rev, path);
+}
+
 void cgit_log_link(char *name, char *title, char *class, char *head,
 		   char *rev, char *path, int ofs, char *grep, char *pattern)
 {