Add prepare release script

Fixes issue #286

Author: sebastianfeldmann

build/release-prepare

@@ -0,0 +1,24 @@
+#!/usr/bin/env php
+<?php
+
+$version = $argv[1] ?? '';
+
+if (empty($version)) {
+  echo "version number is missing\n";
+  exit(1);
+}
+
+$root = realpath(__DIR__ . '/..') . '/';
+$file = $root . 'src/CH.php';
+$ch   = file_get_contents($file);
+$date = date('Y-m-d');
+
+$ch = preg_replace("~VERSION = '[0-9]+\.[0-9]+.[0-9]';~", "VERSION = '$version';", $ch);
+$ch = preg_replace("~RELEASE_DATE = '[0-9]+-[0-9]+-[0-9]+';~", "RELEASE_DATE = '$date';", $ch);
+
+file_put_contents($file, $ch);
+
+`git add $file`;
+`git commit -m'Prepare version $version'`;
+`git tag -asm'Version $version' $version`;
+