portlint makes a small set of sanity checks for port directory.

usage: portlint [-abctvN] [-B#] [port_directory]
        -a      additional check for scripts/* and pkg/*
        -b      warn $(VARIABLE)
        -c      committer mode
        -v      verbose mode
        -t      nit pick about use of spaces
        -N      writing a new port
        -B#     allow # contiguous blank lines (default: 1 line)