Allow writing to stdout.

`fcp ... - ` will now write a tarball to stdout in case you want to tar up a
directory or whatever and not extract it again in the receiving side.

Note that `fcp ... somehost:-` isn't explicitly disallowed but it would just
end up going to /dev/null anyway (see rpc()).
Allow globs in the source path specefication.

Now you can us eg `fcp somehost:~/foo*.tiff .` and have all the globbed files
transferred over. Note that you can ONLY put globs in the basename (ie, not in
any of the parent directory specifications). `find` is used for the glob
matching. On my machine that just calls out to libc's fnmatch() function.

Now passing the files to be transferred to tar via stdin (with the -I arg)
because the glob could produce multiple matches. Also there is a check or two
in the result of the glob that don't really expect it to be multiple lines but
also don't seem to break if that is the case.
Update docs.
Update docs re bash completion.