Installation directory

[anthonysteed]

For Windows 10, the installation directory should now be:

<user_dir>\Documents\OpenSCAD\libraries

Other version of windows must vary, but it should be in the default OpenSCAD library directory (https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Libraries), but that is also slightly wrong, in that "My Documents" is now just "Documents". But one of <user_dir>\Documents\OpenSCAD or <user_dir>\My Documents\OpenSCAD should already exist (OpenSCAD creates it and put "backups" in there), "libraries" will need to be created by hand.

Thanks.