Fix bug in global declarations.
Fix bug in global declarations.

Top level import from as not taken into account.

artas360/pythran,hainm/pythran,pombredanne/pythran,pbrunet/pythran,artas360/pythran,pombredanne/pythran,hainm/pythran,serge-sans-paille/pythran,hainm/pythran,pbrunet/pythran,artas360/pythran,pbrunet/pythran,serge-sans-paille/pythran,pombredanne/pythran