Visual Studio solution: Set InlineFunctionExpansion to
OnlyExplicitInline ("/Ob1" option) on all projects (in
pyproject.props) in Debug mode on Win32 and x64 platforms to expand
functions marked as inline.

This change should make Python compiled in Debug mode a little bit
faster on Windows. On Unix, GCC uses -Og optimization level for
./configure --with-pydebug.