new file:   COPYRIGHT
	new file:   session.c
	new file:   session.h

out_port now a session context is looped through everything

(like .305) or other tokens like .3sd2, which should be a symbol
name.

long/long double duality mostly completed including range checks for keeping the integer property; new observation regarding gc noted in TODO

property of numbers, so we can treat numbers that are actually
integers differently, e. g. not print them in exponential representation

made time and measure return the value of the evaluated forms; made
errset return the error message as a string; renamed get_symbol(_z)
to intern(_z)

comments for the builtins.

rewarding); builtins now get the number of arguments passed, which
we have anyway; trace-function and the related bit; port name is
no longer a Lisp string (no reason why it should be); s_expr now
exported from the printer

New ob_common.c for operations common to all object types, mainly
memory management including freelists and stuff. New "next" field
in the Lobject_t provides linkage for allocated and free lists. New
tunables.h to contain tunable parameter defines. make_ and
restore_bindungs now uses pushdown lists instead of a map for every
stack frame, should be much faster and provides GC protection. The
next field in the Lobject_t necessitated a changes in the hashmap,
as this field is different for every object. In the process fixed
a bug in make_bindings that made one binding too many -- bound nil
to nil, and one that called restore_bindings wrongly when there
were too many (or too few?) function parameters. Some gc stuff
begun, but far from doing something. gc_protect stuff in a very
indefinite state, but thankfully it isn't called anywhere yet. New
object type GCPROT, not ever Lisp-visible. Fixed describe which
reliably followed every cycle of cyclic references (e. g. the nil
object). And some minor stuff.

by putting them on a protect stack

for symbols (as before for strings); make describe print information
about the name of a symbol

interpreter (like the other measures), not since start of the epoch