Rearrange order of subdirectory creation to help generate parse.h

Rearrange order of subdirectory creation to help generate parse.h
 file early enough to use in nodes/.
Try to be more complete for rules on generating parse.h,
 but it still does not work any better than before. Should be able to
 make correctly if parser/gram.y is updated even without a "make clean"
 but so far not there yet.