Adding the ability to send in pre-compiled dox source

Instead of `options.source` being a directory, it can now either be a directory (string) or it can be an array of objects in the following format:

```javascript
{
  name: '...', // required, name of the resource being documented
  dox: [...], // required, array of dox comments for the resource.  This is a substitute for the output of the parser
  targetName: '...' // optional, name of the output file.  Defaults to [name].[target_extension], where target_extension is set from the options to doxx
}

Essentially, this allows the user to specify if they want to use the default dox parser engine in doxx, or if they want to compile the dox themselves and use the doxx engine for compilation of the output files.