Move Atlas map settings from JS to C++.

Replace New dialog box with separate tools for resizing maps and
replacing terrain textures, to provide more power and to simplify the
problem of initialising map settings.
Fix engine to cope with dynamic map resizing.
Add JSON support to AtObj, to let C++ interact with JSON more easily.

This was SVN commit r9566.

source/tools/atlas/AtlasScript/ScriptInterface.cpp

@@ -609,6 +609,8 @@ AtlasScriptInterface_impl::AtlasScriptInterface_impl()
 		| JSOPTION_XML // "ECMAScript for XML support: parse <!-- --> as a token"
 		);
 
+	JS_SetVersion(m_cx, JSVERSION_LATEST);
+
 	m_glob = JS_NewGlobalObject(m_cx, &global_class);
 	JS_InitStandardClasses(m_cx, m_glob);