gfse: use POST requests when parsing grammar modules after editing as text

instead of GET, to avoid the Apache httpd URI length limitation.

This means that gfse can no longer use JSONP when parsing grammars, so it
has to be located on the same host as the cloud service.

Also clean away trailing white space in support.js.

src/www/gfse/cloud2.js

@@ -259,7 +259,8 @@ function gfshell(cmd,cont) {
 // Check the syntax of a source module
 function check_module(path,source,cont) {
     var enc=encodeURIComponent;
-    http_get_json("/parse?"+enc(path)+"="+enc(source),cont)
+    //http_get_json("/parse?"+enc(path)+"="+enc(source),cont)
+    ajax_http_post_json("/parse",enc(path)+"="+enc(source),cont)
 }
 
 // Check the syntax of an expression