Source for conversion is down

[Flowgram]

http://rate-exchange.appspot.com/ is returning:

Error: Not Found
The requested URL / was not found on this server.

[Flowgram]

This pull request: #5 is meant to solve the issue but I'm getting this error:

Fatal error: Maximum function nesting level of '100' reached, aborting! in ....\PHP-Currency-Convert-Class\classes\convert.php on line 151