Support dynamic salt lengths in ISPConfig password driver

[sguter90]

This fixes the "CouldNotSaveNewPassword" error when changing password via settings for mailboxes created/updated in newer ISPConfig versions.

Additionally:

• Splits logic into smaller methods
• Adds log method to avoid same ifs
• Adds more log output in case of errors
• Updates cryptPassword to behave the same as in ISPConfig (more secure salt generation)
• Fixes some code styles

This should fix: https://github.com/RainLoop/rainloop-webmail/issues/2072 https://github.com/RainLoop/rainloop-webmail/issues/1946

Should include all fixes according ISPConfig solved in some other way in: https://github.com/RainLoop/rainloop-webmail/pull/2095

This still doesn't add support for multi server environments: https://github.com/RainLoop/rainloop-webmail/issues/733

I implemented the code with a PHP language level of 7.0. Everything above is supported. Wasn't sure if there are any style rules but I did my best to match with the style used in other plugins.

I tested the code with a local environment and on production servers. The password salt detection is backwards compatible with old passwords using a fixed salt length. So this shouldn't have any side effects on existing installations.

[lol-deb]

Hello, I just wanted to confirm that the patch works for me. Debian Bullseye - ISPConfig 3.2.8p1 - Rainloop 1.16.0 It solved https://github.com/RainLoop/rainloop-webmail/issues/2072 Thank you.