Upgrading from 4.x to 5.x

[Daniel Miller]

Hi!

I'm a very inexperienced user with Solr.  I've been using Solr to 
provide indexes for my Dovecot IMAP server.  Using version 3.x, and 
later 4.x, I have been able to do so without too much of a challenge.  
However, version 5.x has certainly changed quite a bit and I'm very 
uncertain how to proceed.

I currently have a working 4.10.3 installation, using the "example" 
server provided with the Solr distribution package, and a schema.xml 
optimized for Dovecot.  I haven't found anything on migrating from 4 to 
5 - at least anything I actually understood.  Can you point me in the 
right direction?

--
Daniel