Libdwarf version 0.5.0

libdwarf-0.5.0 improves library performance reading
DWARF DIEs by several percent (with no change in API).

It adds functions allowing acess to the .debug_addr
section independent of other sections.
dwarfdump has a new option to show that
section.

Corrects the handling of some aspects of
reading the .debug_names section.

Enhances dwarf_get_globals() to return
all globals that .debug_pubnames and .debug_names
refer to (no change in the API except adding
a function to return the DW_TAG of any globals
derived from .debug_names)