fix wget error when downloading data file

There is an error with wget when trying to download geodata file. 
```
Resolving cloud.github.com (cloud.github.com)... 54.230.69.175, 54.230.68.59, 54.230.69.207, ...
Connecting to cloud.github.com (cloud.github.com)|54.230.69.175|:443... connected.
OpenSSL: error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure
Unable to establish SSL connection.
```

Which can be resolved using curl on my computer, I hope it will work on travis !