Upgrade hash algo to use password_hash/password_verify

[Script47]

@ChristopherDay

Added a backward compatible way to update the hash algo from sha256 to use the preferred password_hash/password_verify methods.

• Introduced two new methods hash_password($var) and verify_password($salt, $password, $compareTo = null) and deprecated the old encode method
• Removed the user ID salt as password_hash handles salt generation

I've tested login and register with both passwords using the old algo and the new one but can't test forgot password locally, though, theoretically it should work as login and register do.

[T-Tron]

Works - Perfect Code.