Do not require javascript-enabled clients

A simple submit-button is all that's required to make the branch selector
drop-down work on any client, so lets add one.

Noticed-by: Olivier Ramonat <olivier@ramonat.fr>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
diff --git a/ui-shared.c b/ui-shared.c
index ca8dd3d..bd34cc3 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -487,9 +487,13 @@
 		html("<p>\n<h1>branch</h1>\n");
 		html("<form method='get' action=''>\n");
 		add_hidden_formfields(0, 1, cgit_query_page);
+		html("<table class='grid'><tr><td id='branch-dropdown-cell'>");
 		html("<select name='h' onchange='this.form.submit();'>\n");
 		for_each_branch_ref(print_branch_option, cgit_query_head);
 		html("</select>\n");
+		html("</td><td>");
+		html("<input type='submit' id='switch-btn' value='..'>\n");
+		html("</td></tr></table>");
 		html("</form>\n");
 
 		html("<p>\n<h1>search</h1>\n");