Use curl instead of wget

Curl builds and runs on lots of more platforms than wget. For example: OS/400, TPF and other more "exotic" platforms that aren't straight-forward unix clones.

Curl supports more protocols: FTP, FTPS, HTTP, HTTPS, SCP, SFTP, TFTP, TELNET, DICT, LDAP, LDAPS, FILE, POP3, IMAP, SMTP, RTMP and RTSP. Wget only supports HTTP, HTTPS and FTP.

Also has other advantages over the wget: http://daniel.haxx.se/docs/curl-vs-wget.html