Set debian-sys-maint password after grant

- If a new data dir is initialized, there wont be a debian-sys-maint
user created, so the recipe fails trying to set a password to a
nonexistent user. This change makes it succeed.
Kitchen suite for new datadir

- previously installing with a new data dir was broken. that fix
aside, lets test that to make sure it stays working
- bump vm memory, otherwise mysql gets oom'ed on install
Merge pull request #142 from iancoffey/debiangrants

Debiangrants

closes #139
add contribution from @iancoffey to the README
add guards for cluster and backup where access_grants is included
add contribution from @notnmeyer to the README
Merge pull request #146 from phlipper/honor_skip_passwords

Honor skip passwords

closes #145
closes #104
use replication username attribute rather than 'repl' 

the /etc/mysql/replication.sql file should use the percona.server.replication.username attribute rather than the hardcoded 'repl'for the replication username
add contribution from @odacrem to the README
Merge pull request #147 from phlipper/replication-username

use replication username attribute

closes #141
attribute to skip auto configure

- add option to skip auto-configuring after percona::server is
called, so pre-config work can be done if needed
some readme action

- detail about skip_configure for the readme
add contribution from @iancoffey to the README
Merge pull request #149 from phlipper/skip_config

attribute to skip auto configure

closes #143
bump version to 0.15.2
update gems
cleanup and update Berksfile
cleanup and unify file comment headers
remove constants:

* there were many warnings about constants being
  reassigned, and these are not being used in any
  other context, so they have been converted to 
  local variables
clean up recipe, guided by tests