Add new features to the config command for control of the config file:

- manipulate the autoexec section
- display information on sections and values
- show the used config files and startup command line parameters 
- restart capability
- save config files either in the config or program directory

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3651

include/cross.h

@@ -74,6 +74,7 @@ public:
 	static void CreatePlatformConfigDir(std::string& in);
 	static void ResolveHomedir(std::string & temp_line);
 	static void CreateDir(std::string const& temp);
+	static bool Cross::IsPathAbsolute(std::string const& in);
 };