Automake-1.5 chokes on gst/Makefile.am, so updating requirement to 1.6.

Original commit message from CVS:
Automake-1.5 chokes on gst/Makefile.am, so updating requirement to
1.6.
diff --git a/REQUIREMENTS b/REQUIREMENTS
index 9cfdfea..0bdcebb 100644
--- a/REQUIREMENTS
+++ b/REQUIREMENTS
@@ -29,7 +29,7 @@
 CVS (using autogen.sh):
 
 autoconf 2.52
-automake 1.5
+automake 1.6
 libtool v1.4 or better
 pkgconfig 0.9.0 (http://www.freedesktop.org/software/pkgconfig/)
 
diff --git a/autogen.sh b/autogen.sh
index 18633ed..f37285b 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -27,8 +27,8 @@
 if test ! -z "$NOCHECK"; then echo ": skipped version checks"; else  echo; fi
 version_check "autoconf" "$AUTOCONF autoconf autoconf-2.54 autoconf-2.53 autoconf-2.52" \
               "ftp://ftp.gnu.org/pub/gnu/autoconf/" 2 52 || DIE=1
-version_check "automake" "$AUTOMAKE automake automake-1.7 automake-1.6 automake-1.5" \
-              "ftp://ftp.gnu.org/pub/gnu/automake/" 1 5 || DIE=1
+version_check "automake" "$AUTOMAKE automake automake-1.7 automake-1.6" \
+              "ftp://ftp.gnu.org/pub/gnu/automake/" 1 6 || DIE=1
 version_check "libtool" "" \
               "ftp://ftp.gnu.org/pub/gnu/libtool/" 1 4 0 || DIE=1
 version_check "pkg-config" "" \