gfse: grammars can now contain one-line descriptions

Also fixed two small problems with public grammars.

src/www/gfse/editor.css

@@ -45,6 +45,9 @@ div.namebar table { width: 100%; }
 .namebar h3, .sheet h3 { margin: 0; color: #009; }
 .home h3 { margin-top: 0; color: #009; }
 
+div.comment:before { content: "-- "; }
+div.comment { color: #009; margin-left: 1em; }
+
 td.right { text-align: right; }
 td.center { text-align: center; }
 

src/www/gfse/editor.js

@@ -98,7 +98,7 @@ function draw_grammar_list() {
 	    var pubspan=[span_class("more",pub)]
 	}
 	return edtr([td(delete_button(del(i),"Delete this grammar")),
-		     td(title(gid.unique_name,link)),
+		     td(title(gid.unique_name || "",link)),
 		     td(more(clone(i),"Clone this grammar")),
 		     td(pubspan)
 		    ])
@@ -161,6 +161,7 @@ function draw_grammar_list() {
 
 function new_grammar() {
     var g={basename:"Unnamed",
+	   comment:"",
 	   extends:[],
 	   uextends:[],
 	   abstract:{cats:[],funs:[]},
@@ -226,6 +227,7 @@ function open_public(file) {
 	delete g.index
 	delete g.unique_name
 	delete g.publishedAs
+	if(!g.uextends) g.uextends=[]
 	reload_grammar(g)
     }
     var parts=file.split(/[-.]/)
@@ -286,7 +288,10 @@ function draw_namebar(g,files) {
     return div_class("namebar",
 		     [table([tr([td(draw_name(g)),
 				 td_center(center),
-				 td_right(right)])])])
+				 td_right(right)]),
+			     tr([attr({colspan:"3"},td(draw_comment(g)))])
+			    ])
+		     ])
 }
 
 function draw_name(g) {
@@ -803,6 +808,10 @@ function draw_abstract(g) {
     return file;
 }
 
+function draw_comment(g) {
+    return div_class("comment",editable("span",text(g.comment || ""),g,edit_comment,"Edit grammar description"));
+}
+
 function module_name(g,ix) {
     return ix==0 ? g.basename : g.basename+g.concretes[ix-1].langcode
 }
@@ -1046,6 +1055,15 @@ function edit_name(g,el) {
     }
     string_editor(el,g.basename,change_name)
 }
+
+function edit_comment(g,el) {
+    function change_comment(comment) {
+	g.comment=comment
+	reload_grammar(g);
+	return null;
+    }
+    string_editor(el,g.comment || "",change_comment)
+}
 /* -------------------------------------------------------------------------- */
 
 function draw_concrete(g,i) {

src/www/gfse/gf_abs.js

@@ -9,6 +9,7 @@ type FunId = Id -- function name
 type Type = [Cat] -- [Cat_1,...,Cat_n] means Cat_1 -> ... -> Cat_n
 
 type Grammar  = { basename: ModId,
+                  comment: String,
                   extends: [ModId], -- in 1-to-1 correspondence with uextends
 		  uextends: [UniqueId], -- added 2012-10-16
                   abstract: Abstract,