Add some long options.

Currently, they're all aliases for existing short options, but we're out
of letters, so we'll be adding some that won't have short options.

This means we can't have entries in the options table corresponding to
short options with no long options, as an entry in the long options
table with a null option name terminates the table.
For all options with arguments, mention the argument.

In the detailed list of options, if an option takes an argument, list it
in the summary of the option.

Also, --list-interfaces corresponds to -D, not -d.
Merge git://github.com/the-tcpdump-group/tcpdump
We no longer have win32/Include/errno.h.