new file types to add

[jmripper]

Was hoping to add in a few more file types to this lib.

pcap hex: D4 C3 B2 A1 & hex: A1 B2 C3 D4 ext: pcap mime: 'application/vnd.tcpdump.pcap'

cfbf hex: D0 CF 11 E0 A1 B1 1A E1 multiple exts: doc, xls, ppt, msi, msg multiple mime types

Thanks!