Run "TZ=UTC0 admin/update-copyright".

With the removal of unexec and purespace, the definitions in these files
are no longer used.  Remove them.

* src/firstfile.c:
* src/lastfile.c: Delete unused files.
* configure.ac (PRE_ALLOC_OBJ, POST_ALLOC_OBJ, FIRSTFILE_OBJ):
Remove variables and dependent code.
* msdos/autogen/Makefile.in:
* msdos/sed1v2.inp:
* src/Makefile.in: Don't use above deleted variables.
* src/deps.mk: Remove lastfile.c dependencies.

* configure.ac (CYGWIN_OBJ): Remove comment.
* src/Makefile.in (PAXCTL, SETFATTR, PAXCTL_dumped, PAXCTL_notdumped):
Remove definitions.
(emacs$(EXEEXT), temacs$(EXEEXT), bootstrap-emacs$(EXEEXT)):
* src/deps.mk: Remove 'unexec'-specific code.

* src/alloc.c (pure, PUREBEG, purebeg, pure_size)
(pure_bytes_used_before_overflow, pure_bytes_used_lisp)
(pure_bytes_used_non_lisp): Remove definitions.
(init_strings): Make empty strings impure.
(cons_listn): Drop 'cons' argument.
(pure_listn): Remove function.
(init_vectors): Allocate zero vector manually to avoid freelist issues.
(pure_alloc, check_pure_size, find_string_data_in_pure)
(make_pure_string, make_pure_c_string, pure_cons, make_pure_float)
(make_pure_bignum, make_pure_vector, purecopy_hash_table): Remove
functions.
(purecopy): Reduce to hash consing our argument.
(init_alloc_once_for_pdumper): Adjust to lack of pure space.
(pure-bytes-used): Adjust docstring to mark as obsolete.
(purify-flag): Keep for hash consing, but adjust docstring.
* src/bytecode.c:
* src/comp.c: Don't include "puresize.h".
* src/conf_post.h (SYSTEM_PURESIZE_EXTRA): Remove definition.
* src/data.c (pure_write_error): Remove function.
* src/deps.mk: Remove puresize.h dependency throughout.
* src/emacs.c:
* src/fns.c:
* src/intervals.c:
* src/keymap.c: Don't include "puresize.h".
* src/lisp.h (struct Lisp_Hash_Table): Adjust comment.
(pure_listn, pure_list, build_pure_c_string): Remove.
* src/w32heap.c (FREEABLE_P): Don't do use 'dumped_data'.
(malloc_before_dump, realloc_before_dump, free_before_dump): Remove
functions.
* src/w32heap.h: Adjust prototype.
* lisp/loadup.el:
* lisp/startup.el: Remove purespace code.

* src/Makefile.in (base_obj): Add sort.o.
* src/deps.mk (fns.o): Add sort.c.
* src/lisp.h: Add prototypes for inorder, tim_sort.
* src/sort.c: New file providing tim_sort.
* src/fns.c:  Remove prototypes for removed routines.
(merge_vectors, sort_vector_inplace, sort_vector_copy): Remove.
(sort_list, sort_vector): Use tim_sort.
* test/src/fns-tests.el (fns-tests-sort): New sorting unit tests.

Run "TZ=UTC0 admin/update-copyright".