refactor path interface:

- use wrapper class instead of std::wstring (reduces mixing of
strings/paths; allows safe+easy join via operator/ and convenient
case-insensitive comparison via operator==, avoids NativePathFromString,
similar to boost::filesystem)
- NativePath -> OsPath
- add hash and To/FromJSVal for Path
- add TS_ASSERT_PATH_EQUALS
- replace _wfopen_s with sys_OpenFile
- remove obsolete SortFiles/Directories

This was SVN commit r9107.

source/scripting/ScriptingHost.cpp

@@ -94,7 +94,7 @@ void ScriptingHost::RunScript(const VfsPath& pathname, JSObject* globalObject)
 	jsval rval;
 	JSBool ok = JS_EvaluateUCScript(m_Context, globalObject,
 		reinterpret_cast<const jschar*>(script.c_str()), (uintN)script.size(),
-		CStrW(pathname).ToUTF8().c_str(), 1, &rval);
+		utf8_from_wstring(pathname.string()).c_str(), 1, &rval);
 
 	if (ok == JS_FALSE)
 		throw PSERROR_Scripting_LoadFile_EvalErrors();