fix missing tbox.dll at runtime with msvc and windows

fpm/__init__.py

@@ -2,6 +2,7 @@
 # fpm module initialization file
 
 import fwk
+import tbox # on windows, preloads tbox.dll so that it is found later by fpmw.dll 
 fwk.wutils.findbins('fpm', verb=False)
 
 from fpmw import *