Add defuse/php-encryption 2.0 to Composer dependencies

vendor/bin/generate-defuse-key

@@ -0,0 +1,17 @@
+#!/usr/bin/env sh
+
+dir=$(d=${0%[/\\]*}; cd "$d"; cd "../defuse/php-encryption/bin" && pwd)
+
+# See if we are running in Cygwin by checking for cygpath program
+if command -v 'cygpath' >/dev/null 2>&1; then
+	# Cygwin paths start with /cygdrive/ which will break windows PHP,
+	# so we need to translate the dir path to windows format. However
+	# we could be using cygwin PHP which does not require this, so we
+	# test if the path to PHP starts with /cygdrive/ rather than /usr/bin
+	if [[ $(which php) == /cygdrive/* ]]; then
+		dir=$(cygpath -m "$dir");
+	fi
+fi
+
+dir=$(echo $dir | sed 's/ /\ /g')
+"${dir}/generate-defuse-key" "$@"