Fix reported and outstanding bugs. Reformat some text for

Fix reported and outstanding bugs. Reformat some text for
readability/understandability. Assembles new instructions  for G and H
format floating numbers & new queue instructions
asscan.c split into 4 files; two additional files to construct and
manipulate G and H format numbers, with analog for atof()
Numerical accuracy of new atof() not verified; standard atof() used
for F and D floating numbers.  As does NOT use G and H instructions itself

SCCS-vsn: old/as.vax/ascode.c 4.8
SCCS-vsn: old/as.vax/asexpr.c 4.3
SCCS-vsn: old/as.vax/asio.c 4.4
SCCS-vsn: old/as.vax/asjxxx.c 4.6
SCCS-vsn: old/as.vax/asmain.c 4.9
SCCS-vsn: old/as.vax/asparse.c 4.8
SCCS-vsn: old/as.vax/aspseudo.c 4.4
SCCS-vsn: old/as.vax/assyms.c 4.7
SCCS-vsn: old/as.vax/as.h 4.9
SCCS-vsn: old/as.vax/asexpr.h 4.3
SCCS-vsn: old/as.vax/asscan.h 4.4
SCCS-vsn: old/as.vax/assyms.h 4.3
SCCS-vsn: old/as.vax/Makefile 4.3
SCCS-vsn: old/as.vax/asscanl.h 4.3
SCCS-vsn: old/as.vax/asscan1.c 4.3
SCCS-vsn: old/as.vax/asscan2.c 4.3
SCCS-vsn: old/as.vax/asscan3.c 4.3
SCCS-vsn: old/as.vax/asscan4.c 4.3
SCCS-vsn: old/as.vax/assizetab.c 4.3
SCCS-vsn: old/as.vax/bignum1.c 4.3
SCCS-vsn: old/as.vax/bignum2.c 4.3
SCCS-vsn: old/as.vax/floattab.c 4.3
SCCS-vsn: old/as.vax/natof.c 4.3
SCCS-vsn: old/as.vax/asnumber.h 4.3
SCCS-vsn: old/as.vax/astoks.H 4.3
SCCS-vsn: old/as.vax/astokfix.awk 4.3