standarizing no params help messages
more help messages

...beginning to doubt overall approach. It's pretty wordy. Contrast
these two:

B:\code\apt>apt download

Download the package(s) from mirror and save in local cache folder:

    C:\> apt download shell gdal {...etc}

    shell = d:/temp/o4w-cache/setup/http%3a%2f%2fdownload.osgeo.org%2fosgeo4w%2f
/x86/release/shell/shell-1.0.0-13.tar.bz2
    remote:  c38f03d2b7160f891fc36ec776ca4685  shell-1.0.0-13.tar.bz2
    local:   c38f03d2b7160f891fc36ec776ca4685  shell-1.0.0-13.tar.bz2

    gdal = d:/temp/o4w-cache/setup/http%3a%2f%2fdownload.osgeo.org%2fosgeo4w%2f/
x86/release/gdal/gdal-1.11.1-4.tar.bz2
    remote:  3b60f036f0d29c401d0927a9ae000f0c  gdal-1.11.1-4.tar.bz2
    local:   3b60f036f0d29c401d0927a9ae000f0c  gdal-1.11.1-4.tar.bz2

    Use `apt available` to see what is on the mirror for downloading.


*** No package names specified. ***

B:\code\apt>apt find
Find what? Enter a filename to look for (partial is ok).
still looking for "best" help text
apply Google Style Guide for docstrings
allow dotted notation for "dists" master dictionary

Using module from https://github.com/bcj/AttrDict. The class I was using
from Stack only seemed to work for top level.

One observed drawback is that a varname can't be used in the middle:

Dict syntax:    dists[distname]['gdal'] --> works
Dict syntax:    dists['curr']['gdal']   --> works

Attr syntax:    dists.distame.gdal      --> fails
Attr syntax:    dists.curr.gdal         --> works
move get_info innards into parse_setup_ini

...because otherwise we don't have the atomized fields (md5, zip_path,
etc.) in the global "dists" dict. Lots of debug code still all over the
place.
remove some cruft

hopefully https://github.com/bcj/AttrDict/issues/16 yields some fruit