[C] Update ColouredConsoleSender to support colored conversations. Fixes BUKKIT-5487.

### The Issue
Starting a conversation with a ColouredConsoleSender doesn't allow you to actually send colors.

### Justification for this PR
Allows you to have conversations with a coloured console in color, which adds depth and helps usability in many different plugin scenarios. 

### PR Breakdown
Override sendRawMessage in ColouredConsoleSender and changed sendMessage to delegate to it (as both Player and non-color console senders do).

### Testing Results and Materials
Test plugin: https://gist.github.com/nightpool/9755955

![Picture of test plugin running on sever](http://i.imgur.com/a19RxUl.png)

BUKKIT-5487 - https://bukkit.atlassian.net/browse/BUKKIT-5487