DIP 1019--Named Arguments Lite--Community Review Round 1

[Yuxuan Shui]

After thinking about the feedback so far, I currently plan to 
make these changes to this DIP:

* For reordering: I want to step back from reordering. It was add 
as an after thought, and turns out to be way more involved than I 
expected, and it is really not part of my goal for this DIP.

* For @named: Since there exist templates like 
ParameterIdentiferTuple, it shouldn't be hard to write a template 
to automatically wrap non- at named functions to make them @named. 
So this really is not a problem.

   If you are not satisfied with this solution (let me know), I 
have another proposal: @named will still be part of this DIP, but 
if a function is not annotated with @named, you can still call it 
with named parameters. If the names mismatch, you get a warning 
instead of an error. This way, API developers can clearly state 
their intentions with @named, and don't have to take 
responsibilities for API breakage caused by parameter rename; 
OTOH, API users can still call functions with named parameters.