modify build.py to produce installers

[abrichr]

We would like to implement automatic updates. Without installing to a system directory, however, this is not user friendly (see #782 (comment)).

This PR implements functionality to produce an installer so that the installed application can be updated more easily.

[KIRA009]

This looks good, tested on Mac. We might also have to change the ci scripts, unless the dmg making process is using stuff that comes pre-installed with the mac image

[abrichr]

Thank you @KIRA009 !

We might also have to change the ci scripts, unless the dmg making process is using stuff that comes pre-installed with the mac image.

Can you please clarify?

Edit: Understood, I believe hdiutil is included in the standard MacOS installation. I've modified the CI scripts to remove zipping as well.

[abrichr]

@KIRA009 I believe we should modify the Github actions to remove the zipping functionality, since Inno Setup already seems to compress the setup file, and I believe .dmg files are also compressed. What do you think?

Edit: we will also need to modify the website to point to these new files.