Introduced platform info for amazon version 2014.09

This patch adds in package name settings for amazon version 2014.09. Note I have only tested this with mysql version 5.5. I've done no sort of testing of this code (kitchen?), other than running my chef script.

Disclaimer: I'm not primarily a ruby developer, but I can get by.

I'm sure there is a better way of managing amazon versions, as they will change in a matter of months. Perhaps make the highest version the default? ...so future versions at least return something.

It was very hard to figure out what was wrong with code like this:
```
      rescue NoMethodError
        nil
      end
```
...which meant that I wasn't getting any errors thrown when I needed them.

I'm guessing this issue is very close to #229 ,  I think lines 94 and 97 should also be `mysql-server`.
**Edit**: I think my second commit actually resolves #229. Amazon doesn't need the yum-mysql-community repo. It makes the assumption that it has never been needed for any amazon version.