move code over from Postfixadmin ( https://github.com/postfixadmin/postfixadmin/blob/feature-improve-pacrypt/model/PFACrypt.php ), tidy up

Author: DavidGoodwin

README.md

@@ -1,2 +1,29 @@
-# pacrypt
-standalone PHP library for creating various password hashes
+# PostfixAdmin\PasswordHashing
+
+Standalone PHP library for creating various password hashes
+
+Note, this library is still quite new (2021/07/02). It's quite likely to have major refactoring / renaming as it's reviewed.
+
+
+## Example usage
+
+```PHP
+$tool = new \PostfixAdmin\PasswordHashing\Crypt();
+
+// should output something to indicate what your system supports (may be dependent on PHP variant, PHP modules etc)
+var_dump($tool->supportedMechanisms()); // e.g. MD5, SHA1, ARGON2I. 
+
+var_dump($tool->hash(Crypt::CLEARTEXT, 'fishbeans'));
+
+var_dump($tool->hash(Crypt::MD5, 'fishbeans'));
+
+var_dump($tool->verify(Crypt::MD5, 'fishbeans', 'some-hash'));
+
+var_dump($tool->verify(Crypt::ARGON2I, 'fishbeans', 'some-hash'));
+
+```
+
+
+## ChangeLog
+
+2021/07/03 - Initial release / copying of code from https://github.com/postfixadmin/postfixadmin ...

composer.json

@@ -0,0 +1,33 @@
+{
+    "name": "postfixadmin/password-hashing",
+    "description": "Routines to generate password hashes, useful for Dovecot or Courier Mail servers",
+    "type": "library",
+    "require": {
+        "php": ">=7.2"
+    },
+    "require-dev": {
+        "vimeo/psalm": "^4.8",
+        "phpunit/phpunit": "^8|^9",
+        "friendsofphp/php-cs-fixer" : "*"
+    },
+    "license": "GPLv2",
+    "scripts": {
+        "psalm" : "@php vendor/bin/psalm src",
+        "test" : "@php vendor/bin/phpunit tests",
+        "format" : [
+            "@php vendor/bin/php-cs-fixer fix src ",
+            "@php vendor/bin/php-cs-fixer fix tests"
+        ]
+    },
+    "autoload" : {
+        "psr-4" : {
+            "PostfixAdmin\\PasswordHashing\\" : "src"
+        }
+    },
+    "authors": [
+        {
+            "name": "David Goodwin",
+            "email": "david@codepoets.co.uk"
+        }
+    ]
+}