ZuriHac 2020 project ideas

* Pick one of tasks from our general TODO list in the `README` (some of them have corresponding [issues](https://github.com/nh2/hatrace/issues) already, in such a case please assign the one you take to yourself)
* Implement any syscall you like
* Implement one of the syscalls that we have pre-selected and rated by difficulty in [the gist](https://gist.github.com/qrilka/a910e6aab6250190319913a9d1cf0138). Check out [our guide](https://github.com/nh2/hatrace/blob/master/Adding-new-syscalls.md) for the details how to do this.
* Solve some real-world issues with hatrace and write about them
* [ ] Last year, zappy made a PR (https://github.com/nh2/hatrace/pull/38) that code-generates many useful things, but GHC gets extremely slow on it. Simplifiy it into a single, standalone file not depending on hatrace to turn it into a GHC upstream bug report about this slowness.