Add CHANGES file to distribution

git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@791 f882894a-f735-0410-b71e-b25c423dba1c

Makefile.am

@@ -3,7 +3,7 @@
 SUBDIRS = intl lib plugins plugins-scripts po
 
 EXTRA_DIST = config.rpath \
-	ABOUT-NLS CODING FAQ LEGAL REQUIREMENTS SUPPORT THANKS \
+	ABOUT-NLS CHANGES CODING FAQ LEGAL REQUIREMENTS SUPPORT THANKS \
 	Helper.pm contrib pkg nagios-plugins.spec
 
 ACLOCAL_AMFLAGS = -I lib