Captcha module made more flexable

Hi,

I have made this into more usable and flexable module for generating captcha.

Now the captcha element is created in a service and all options are in the module config.
The captcha generate gets it's own controller class.
The changes make for a more configurable captcha as one is not confined to just images.

You can also specify multiple fonts in an array and it will choose a random one when creating the captcha.

I had trouble with the route so I redid these and it seems to be routing ok access modules.

Thanks for your article, this really solved an problem I was having.

Hope this is OK