Update to accept automake 1.16

(cherry picked from commit 61db4af82d)

INSTALL

@@ -37,7 +37,7 @@ Note for Git checkouts
 -----------------------------
 
 If you have checked this out from Git, you need to have:
-* automake (supported versions are 1.14--1.15)
+* automake (supported versions are 1.14--1.16)
 * autoconf (supported versions are 2.65--2.69)
 Then type "./autogen.sh" to build the needed configuration
 files and proceed as stated above/below.

autogen.sh

@@ -16,11 +16,11 @@ test "$automake_version" != "" && {
 }
 
 case $automake_version in
-    *' '1.1[45]*)
+    *' '1.1[456]*)
 	;;
     *)
 	echo "This automake version is not supported by LyX."
-	echo "LyX only supports automake 1.14 to 1.15."
+	echo "LyX only supports automake 1.14 through 1.16."
 	exit 1
 	;;
 esac

status.23x

@@ -95,3 +95,5 @@ What's new
 
 
 * BUILD/INSTALLATION
+
+- Add support for automake 1.16.