Kpindex

Rewritten FTP code to use yearly data files in different subdirectory rather than the monthly ones.

New dtype used for the binary data too, this may break things for users of older versions!

Fixed FTP issue!

This release may actually work on non-unix platforms!

Thanks for pshustov for the cross-platform code!

This is the initial release which, at the time of release, is able to download all of the Kp index data and includes routines to read these data.