Windows DMD installer

[Daniel Keep]

I actually started sketching out a possible installer a few weeks ago.
Here's what I came up with:

First of all, you can't include DMD itself in the installer since the
license doesn't allow for this.

Secondly, it occurred to me that a program like Cygwin's setup might be
a good idea.  That is, instead of installing a single version of a
single compiler to the machine once, it could be "reusable" and provide
the following:

1. Initial install.

First time, it offers to install a compiler, allowing the user to choose
vendor (obviously only DigitalMars for now), the compiler series (1.x or
2.x), either the latest release, a "bleeding-edge" build (which hasn't
undergone testing yet) or a specific version.

It could also offer to install and configure toolchain components.
That's bud, xfBuild, dsss, maybe even IDEs like Poseidon [1]

2. Management.

If you re-run the installer, it should show your installed compilers and
toolchain programs, check for updates and offer to upgrade them.  It
should also allow you to install another compiler in *addition* to any
existing ones, as well as remove them and select which one goes on the
system/user PATH.

3. Diagnostics.

A lot of people get on the NG or IRC complaining about "Can't find
module object.d"  Most of the time, it's because they decided to be
clever and screwed with the layout of the folders when extracting.  It
would be nice to have a button behind which we could run tests for the
most common broken install problems (you rearranged the directories you
thick burke; why did you think this WOULDN'T break it?!)

As for using an installer "tool", I don't think that's really applicable
for something like this.  I say write it in D because otherwise we'll
have people saying that D sucks because we don't use it.  *sigh*



In a larger context, I think what we should probably do is set up a
website or a portion of the wiki for a "Community Toolchain" project.
Get a list of what D needs, what it needs to do and who is working on it
so that people can contribute more easily.

(I actually think we need a proper community-run front page for D, but
that's for another day.)



[1] You think that should be "Acidosis"?  Really, Thunderbird
spell-checker?  REALLY?