Move the Wiki developer section to the new docs developer page

[shrit]

Hi,

This issue is just a placeholder so we do not forget about this task.

Best,

[plon-Susk7]

Hey @shrit, Can I work on this issue? I am fairly new to using mlpack and would love to contribute more to this project. I have played around with other machine-learning libraries and I'd love to learn more about mlpack. Any advice will be greatly appreciated.