Ckernel

Minor changes

- Correct function signature for `do_execute` so as to not forward `cell_meta` kwarg to `autocompile` (fixes 9).

Minor changes

- Check whether `stdin` redirected by comparing `stream` file descriptor to `stdin` file descriptor and whether `stdin` was redirected to a file (fixes 8).

Minor changes

- Added installation option `--eat-newline` which will turn on old behaviour to eat `stdin` up to the next newline/EOF. This is off by default to fix 3.

Breaking changes

- Streamlined `install` command. Note that kernels installed before v0.5 will no longer work with v0.5 so they should be reinstalled when you update c-kernel.

Major changes

- Replace `ipcqueue` with `sysv_ipc` dependency (to fix 1).

Minor changes

- Moved docs to https://c-kernel.readthedocs.io/en/latest/index.html

Other

- Tested on macOS and Windows (using WSL).

Minor fixes

- Close subprocess' `stdin` and stop waiting for input when user enters "^D\n"

Major changes

**`ckernel install`**

- specify a setup script to be run before the kernel is started with the `--startup` option. Useful if the kernel is installed into a venv or you want to load modules in the kernel's environment.
- give compilation flags to be applied when compiling or linking executables using the `--exe-cflags`, `--exe-cxxflags` and `--exe--ldflags` options.

Fixes

- clarify that user code requiring input should `define _GNU_SOURCE` before `include <stdio.h>`. This is because internal stdio wrappers have this defined, so without it user code may not `define` the same name for the scanf functions.
- fix bugs with printing the banner during initialisation
- change how package resources are fetched for compatability with Python 3.8 & 3.9 importlib.resources