Module search path initialization code for Windows (PC)
contains empty component(s) if Python home is
determined and
registry key "Software/Python/PythonCore/<Python
Version>/PythonPath" of HKLM or HKCU exists but does
not any subkeys as usually the case. This(ese) empyt
componentes
transformed into current directory later causing to
load modules in the current directory in preference to
modules in the installation.

This patch removes this(ese) empty component(s) from
initial module search path.