[Phamm] Upgrading from 0.5.15 to 0.5.17

[Mike Nielsen]

A while back I setup an ubuntu box with postfix, dovecot, and phamm as a 
mailserver which is working just fine.

There were some problems with ubuntu and 0.5.15 dealing with permissions 
to allow users to manage their own passwords.   A recent update to the 
how to I followed now uses 0.5.17 where permissions problem has been 
resolved.

Question:  Being an LDAP novice how do I go about updating phammfrom 
0.5.15 ot 0.5.17?  Is it a matter of installing over the current scheme 
is if it didn't exist?  (Making sure to keep the container names the same?)

More importantly, assuming I screw something up, how can I reverse the 
changes?

Thank you for your time.
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