Feature Request: Have early package installation mechanism

In line with the security concerns, I'm really thinking we need a way to install packages early.

• lets have a location /boot/config/patches
  
• say samba needs updates, so a new samba.txz is released (or taken from Slackware upstream)
  
• we save the package there.
  
• during startup, unraid sees the package (before anything else starts up - before the network even) and applies it - upgrading the contents of the ram disk
  

Of course I see some issues with this as some unRAID installations might become different from other installs of the same "version", but i think this is an important feature /framework to mitigate security issues. or really bad gotcha's with like docker deprecating old versions and what not.

Edit: corrected a typo

The earliest you can get on current systems is using /boot/extra/ for early packages. It is invoked from the /etc/rc.d/rc.local script before any /boot/config/plugins/*.plg are installed, which is also before /boot/config/go script is kicked off that is before emhttp is launched. However, that is all at the very end of what /etc/rc.d/rc.M kicks off, so you still have networking and samba starting before that point.

That's why I'm requesting for an even earlier time - this would allow us to patch key pieces of unRAID - preferably before the networking and multi-user scripts are executed.