Improvements of "gf -server" mode and related setup

"gf -server" mode now contains everything needed to run the minibar and
the grammar editor (including example-based grammar writing).

The Setup.hs script installs the required files where gf -server can find them.
These files have been moved to a new directory: src/www.

The separate server program pgf-http is now obsolete.

src/www/minibar/minibar_online.js

@@ -0,0 +1,25 @@
+// minibar_demo.js, assumes that minibar.js and pgf_online.js have been loaded.
+
+var online_options={
+  //grammars_url: "http://www.grammaticalframework.org/grammars/",
+  //grammars_url: "http://tournesol.cs.chalmers.se:41296/grammars/",
+  //grammars_url: "http://localhost:41296/grammars/",
+  //grammar_list: ["Foods.pgf"], // leave undefined to get list from server
+}
+
+
+if(/^\?\/tmp\//.test(location.search)) {
+  online_options.grammars_url=location.search.substr(1);
+}
+
+var server=pgf_online(online_options);
+
+var minibar_options= {
+  show_abstract: true,
+  show_trees: true,
+  show_grouped_translations: false,
+  default_source_language: "Eng",
+//feedback_url: "feedback.html",
+  try_google: true
+}
+var minibar=new Minibar(server,minibar_options);