Prepare release 0.5.0

Bump version to 0.5.0.

This release breaks source-code compatibility in many places,
which deserves a change to the minor version.

Libtool versioning has already been bumped:
- libaddrxlat in commit 0b3abb5
- libkdumpfile in commit 1db04a5

Signed-off-by: Petr Tesarik <ptesarik@suse.com>

NEWS

@@ -1,5 +1,5 @@
-next
-----
+0.5.0
+-----
   * Support SADUMP file format.
   * Add kdump_open_fd() and kdump_open_fdset(). Keep KDUMP_ATTR_FILE_FD
     for (partial) backward compatibility.

configure.ac

@@ -19,8 +19,8 @@ dnl  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 dnl Package release versioning
 m4_define([pkg_major_version], [0])
-m4_define([pkg_minor_version], [4])
-m4_define([pkg_micro_version], [1])
+m4_define([pkg_minor_version], [5])
+m4_define([pkg_micro_version], [0])
 m4_define([pkg_version],
           [pkg_major_version.pkg_minor_version.pkg_micro_version])