[Review Queue] Mysql, HAProxy

[Chris Glass]

1. The following branch adds a simple backup mechanism to mysql. +1 (I
would land it but since it's one of my first reviews I'll wait for
feedback on here before I do).

https://code.launchpad.net/~jacekn/charms/trusty/mysql/mysql-backups/+merge/245343

2. This branch adds an optional apt source to HAProxy, and seems ok as
well. Note: the automated tests failed initially but it seems simply
to have been a timeout problem with Azure and not a genuine problem,
as a re-run of the tests passed.

This made me realize the haproxy charm should sync charm-helpers to
make use of some newer additions to it, such as retying when the apt
lock cannot be acquired, but that is an independent remark (out of
scope for this particular branch in my opinion). +1'd

https://code.launchpad.net/~free.ekanayaka/charms/trusty/haproxy/custom-apt-source-support/+merge/247116


- Chris