[Distutils] distutils Install.py and install folder

[Riccardo-Maria BIANCHI]

Good morning,

I'm using distutils to package a tool, and I was thinking that it would 
be very useful to have the self.install_lib variable returned in some 
way to the user in the setup.py script, after the call of setup().

In that way the user could automate the creation of the .pth file in 
order to add the installed module folder to the python search path.
This is useful when the user wants to create a stand-alone package, 
working out of the box when unzipping it, without installation in the 
system site-packages/ folder.

The folder name used for the installation is written out on the screen 
at line 615 of the HEAD of Install.py:

===
log.debug(("modules installed to '%s', which is not in "
                      "Python's module search path (sys.path) -- "
                      "you'll have to change the search path yourself"),
                      self.install_lib)
===

So in some ways we could grab it from there and return it to the user.

Many thanks for your kind attention,

Best regards,