Slight formatting cleanup to ensure the docs are rendered and linked
properly.

Signed-off-by: Rahix <rahix@rahix.de>

Instead of "rebooting" Pycardium, hand over control to core 0, notifying
it of a severe failure via epic_exit(253).

Signed-off-by: Rahix <rahix@rahix.de>

Calls to abort() shouldn't make core 1 busy-spin; call epic_exit()
instead.  Fixes #76.

Signed-off-by: Rahix <rahix@rahix.de>

Instead of dropping to REPL and silently requiring the user to return to
menu via button-press, directly call epic_exit(0) when a script
terminates execution normally (i.e. not via exception).

Signed-off-by: Rahix <rahix@rahix.de>

Remove the big endless loop from pycardium main and instead use
epic_exec("") to switch to REPL.  This way, any MicroPython state is
reset and also all hardware will be in a clean reinitialized state.

This also means that pycard10.py will now run scripts in a clean
environment that is not tainted by whatever was running before.

Fixes #212.

Signed-off-by: Rahix <rahix@rahix.de>

Always print the pycardium header and a short message afterwards what
pycardium is about to do.

Signed-off-by: Rahix <rahix@rahix.de>

Closes #36

Closes #210

Signed-off-by: Rahix <rahix@rahix.de>

Signed-off-by: Rahix <rahix@rahix.de>

Create weak links from MicroPython specific implementations of
modules to standard names. I.e. allow `import time` to import
utime module.

It's 44 years since the release of vi and sadly lots of editors still
don't care about trimming off trailing spaces ...

Signed-off-by: Rahix <rahix@rahix.de>

This allows to read and write strings to the config file.