Remove MySQL connection charset property defaults

[tazmaniax]

Fixes

Fixes #1294

Purpose

Removes unneeded default MySQL character encoding and collation properties

Background Context

Latest Connector/J documentation recommends no character encoding and collation properties to be set by default so that these values to be set by the server while not precluding these properties from being overriden by the client if necessary

[xael-fry]

Tests are ko, can you have a look, thanks

[tazmaniax]

@xael-fry I had a look through the Travis log a couple of times and I don't think the issues had anything to do with the changes. When I compared the failed raw log with another successful log the issues seem to be more with resolving the dependency play-codeborne->guice 1.9. Could it just have been a bad run?

[asolntsev]

@tazmaniax Yes, it seems it was just a bad run.
@xael-fry Can you restart the build? I see a warning that build was migrated from travis.org to travis.com ...

[tazmaniax]

For what its worth, I've been using this change in production since I submitted the pull request against MySQL 5.7

[tazmaniax]

@xael-fry can the build be restarted so we can see if the problem is repeated?

[xael-fry]

@tazmaniax I cannot restart the build since travis move to the new url, can force the last commit to trigger the build again?

[tazmaniax]

@xael-fry sorry, is that something you want me to do? Can you clarify? Should I just make a dummy commit to force the build?

[xael-fry]

Yes a dummy commit or a amend and force push. Thanks

[tazmaniax]

Horaah, the build worked :)

[xael-fry]

@tazmaniax Thanks
Merged in master