Logical. If TRUE, all packages will be installed to and loaded from
the libPaths only. If FALSE, then libPath will
be prepended to .libPaths() during the Require call,
resulting in shared packages, i.e.,
it will include the user's default package folder(s).
This can be create dramatically faster
installs if the user has a substantial number of the packages already in
their personal library. Default FALSE to minimize package installing.