Update Nimrod to 0.10.0

Update **Nimrod**, **Jester** and **Nawak** to their latest versions.
- Nawak incorporated its stdlib changes upstream, and is now using and dependent on the nimble package manager and the nim-zmq and nim-uuid package. It was also made compatible with the latest Nim/Nimrod.
- Jester is using its new async (unfortunately there is no scgi support for now).

N.B.: Nimrod the programming language is being renamed Nim when the official 0.10 comes out.
I couldn't find a reference to it in the `README`, so I thought it was an unused artifact that could be deleted.
Maybe we should update the documentation about this (I didn't put such file for Nawak, for example. Maybe I should?).