Fix for Windows cmd

[thchr]

I was trying out Remark.jl on Windows and noticed that their call to open, which uses DefaultApplication.jl, didn't work.

From a bit of searching, it seems the start cmd command needs a title text (https://superuser.com/a/1335757). I'm not really sure whether start is even required here. Anyway, changing this worked for me.
(On the other hand, I don't quite understand why it e.g. works fine with the .txt file from DefaultApplication.test() - which indeed it does.)

Thanks!

[fonsp]

Even better would be:

run(`$(cmd) /c start "" /b $(filename)`; wait = wait)

For start:
/b to not open a new terminal
https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/start

[tpapp]

Is there an issue for Remark.jl?

[rafael-guerra-www]

@tpapp, fyi, currently this package doesn't launch Excel to open *.xslx files in Windows.
However, these files can be opened with @fonsp command above:

run(`cmd /c start "" /b $(filename)`; wait=true)

[tpapp]

Apologies for not resolving this issue for years now. The only excuse I have is that I don't use Windows so I cannot test these things directly.

This PR would need to be rebased, but given the change is small I would recommend opening a new one against current master, preferably with @fonsp's solution if that is the one that works. I promise to review and merge that quickly.