preserve EXPPP variable order

EXPPP was ordering LOCAL variables alphabetically, which in some cases causes caused them to be used before being defined.

626635b and d10d955 preserve the order of LOCAL variables when pretty printing

d4c7d1b changes the pretty printing of SUBTYPE/SUPERTYPE statements such that one type is on each line. Also indents ONEOF statements.

Reported to me by @TRThurman. Originally found by Lothar Klein and reported as [STEP bug 4986](http://www.wikistep.org/bugzilla/show_bug.cgi?id=4986): _Long form generator or Pretty Printer is changing the order of LOCAL variables in rules, functions, procedures_