A missing 'const' in the declaration of *Callback_Func*
in libdwarf.h.in (and libdwarf.h) provoked compiler warnings.
Now the const is added to that char*name argument type
to avoid the compiler warning in the build of libdwarf.

Users of the producer code may find they need to change
a definition/declaration of their code to avoid a
compilaton failure.  Most users do not use that
procuder code in libdwarf and will not be affected.
The dwarfgen copyright changed to BSD3 form.
libdwarf and dwarfdump copyrights are unchanged.
libdwarf: adding support to write .debug_pubtypes
and adding an error code now used by the producer.
dwarfdump: adding support to print .debug_pubtypes
dwarfgen: adding support to read and write .debug_pubnames
and .debug_pubtypes.
Added dwarf_add_AT_reference_b() and dwarf_fixup_AT_reference_die()
and dwarf_add_AT_with_ref_sig8() to libdwarf producer function list.
Documented the new functions in libdwarf2p.1.mm.
If we already have a DW_AT_sibling attribute we take care not
to add a second one.

dwarfgen now supports some 'class reference' forms (local references
and sig8 references, not yet global references).
Fixed dealloc for dwarf_get_pubtypes to avoid duplicate free.
dwarfexample/Makefile: changed -gdwarf-4 to -g

libdwarf/pro_expr.c,libdwarf/pro_forms.c: Fixed two pointer
used-before-null-test bugs found by the STACK tool from MIT.
dicheck -t found lines with pointless trailing
spaces.  Those spaces are now deleted from
libdwarf/pro_section.c
libdwarf/pro_types.c
libdwarf/pro_vars.c
libdwarf/pro_weaks.c

No logic change is involved.
Removing trailing whitespace. no logic change.
pro_forms.c
pro_frame.c
pro_funcs.c
pro_init.c
pro_line.c
pro_macinfo.c
pro_pubnames.c
pro_reloc.c
pro_reloc_stream.c
pro_reloc_symbolic.c
Removed trailing space(s) from many lines.
libdwarf/ChangeLog
libdwarf/pro_expr.h
libdwarf/pro_macinfo.h
libdwarf/pro_reloc.h
libdwarf/pro_reloc_stream.h
libdwarf/pro_reloc_symbolic.h
libdwarf/pro_section.h
libdwarf/pro_types.h
libdwarf/pro_util.h
Removed trailing whitespace. Two formatting
inconsistencies fixed (one each, two places).  No other change.
gennames.c
malloc_check.c
pro_alloc.c
pro_arange.c
pro_die.c
pro_encode_nm.c
pro_error.c
pro_expr.c
pro_finish.c
Removing useless trailing blanks. No other changes.
common.c
dwarf_leb.c
dwarf_string.c
dwarf_stubs.c
dwarf_types.c
dwarf_util.c
dwarf_vars.c
dwarf_weaks.c
dwarfdump/dwarfdump.c: Initialize a local variable to zero and
  move a declaration (avoiding a c99-ism, the code
  is not supposed to be using c99 features).
libdwarf:  gennames.c, added a comment about errno use.
Old ChangeLog renamed ChangeLog2013, new one named ChangeLog
gennames: deleted include of elf.h, it was not needed because
gelf.h is included. Five dwarfgen files.
libdwarf/gennames.c: Fixed a declaration vs statement ordering
problem.  We do not want c99-specific things in libdwarf C.
libdwarf: gcc -ansi found a // and needed getopt.h include
so those now fixed to support older environments (and newer).
dwarfdump:
      * dwarfdump.c: Change // comments to /* */ comments.
      * makename.c: Delete blank line and trailing space. Add cast
        so gcc -ansi compiles without complaint.
      * print_die.c, uri.c: Change // comments to /* */ comments.
      * tag_attr.c: Add getopt.h include so gcc -ansi compiles
        without complaint.
      * tag_tree.c: Add getopt.h and string.h include so gcc -ansi compiles
        without complaint. Add cast so strdup call to avoid warning.
      * addr_map.c: Add cast so strdup call does not cause warning gcc -ansi.
libdwarf: dwarf_ranges.c, dwarf_sort_lines.c: Remove trailing whitespace.
libdwarf:
dwarf_print_lines.c,dwarf_macro.c: Remove trailing whitespace.
dwarf_ranges.c, dwarf_sort_lines.c: Remove trailing whitespace.
dwarf_query.c, dwarf_pubtypes.c: Remove trailing whitespace.
dwarf_original_elf_init.c,dwarf_loc.c: Remove trailing whitespace.
gennames.c: Fix a printf so the generated dwarf_names.c
        does not have a trailing space.
Now using tsearch style calls with
dwarf_tsearch implementation.
Fixed a small memory curruption in dwarfdump2/print_pubnames.cc
Added tsearch directory with various sorts of tree searches
(all written from scratch, not copied from anywhere).
Removed trailing (and useless) whitespace from all the lines
containing it.  Many many files had such.