Update gdb/NEWS in preparation for GDB 7.8 release.

gdb/ChangeLog:

	* NEWS: Change "Changes since GDB 7.7" into "Changes in GDB 7.8".
Set GDB version number to 7.8.

gdb/ChangeLog:

	* version.in: Set GDB version number to 7.8.
Document the GDB 7.8 release in gdb/ChangeLog

gdb/ChangeLog:

	GDB 7.8 released.
Bump GDB version number to 7.8.0.DATE-cvs.

gdb/ChangeLog:

	* version.in: Set GDB version number to 7.8.0.DATE-cvs.
Automatic date update in version.in
Automatic date update in version.in
Automatic date update in version.in
Automatic date update in version.in
Automatic date update in version.in
Automatic date update in version.in
Fix incorrect placement of two Intel gdb/NEWS items

there were two commits which placed new gdb/NEWS items to the bottom of the
NEWS file (such as for gdb-4.0) instead at their right place under:
	*** Changes in GDB 7.8

https://sourceware.org/git/?p=binutils-gdb.git;a=blobdiff;f=gdb/NEWS;h=ae84e009b8008f9da2707829c0cbab358abc17fb;hp=a8ae8c7b7a5ddce9b5779914dd1e6a87463d7d60;hb=ca8941bbd088002cb8ff87abe16d02ecc8d58d1e;hpb=489e41ddf4bb5616a7471fb4072df5efbb9a706e
commit ca8941bbd088002cb8ff87abe16d02ecc8d58d1e
Author: Walfred Tedeschi <walfred.tedeschi@intel.com>
Date:   Tue Dec 3 13:31:03 2013 +0000
    Documentation for MPX.
Message-Id: <1386074172-14177-1-git-send-email-walfred.tedeschi@intel.com>
https://sourceware.org/ml/gdb-patches/2013-12/msg00082.html

and

https://sourceware.org/git/?p=binutils-gdb.git;a=blobdiff;f=gdb/NEWS;h=a7067fdf9a7af422572a29d1fdd6ef011c87cd9f;hp=b72d64db313d0785edec19a9c4b441b854698e6a;hb=01f9f808e2e86187c95e7cff4aeb014a421a53ce;hpb=93ee1e3683a12f4774b8beb4f821910982e21ce2
commit 01f9f808e2e86187c95e7cff4aeb014a421a53ce
Author: Michael Sturm <michael.sturm@intel.com>
Date:   Mon Dec 16 16:43:05 2013 +0100
    Add AVX512 registers support to GDB and GDBserver.
Message-Id: <1398258160-9070-4-git-send-email-michael.sturm@intel.com>
https://sourceware.org/ml/gdb-patches/2013-12/msg00818.html

gdb/
2014-08-04  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* NEWS (Changes in GDB-4.0): Move Intel MPX and Intel AVX-512 items ...
	(Changes in GDB 7.8): ... here.

Message-ID: <20140804165708.GA12824@host2.jankratochvil.net>
Automatic date update in version.in
Automatic date update in version.in
Automatic date update in version.in
Automatic date update in version.in