I had some time to look at the pacakge, and produced some notes and a
patch file, before realizing that it would be a good idea to consult
with you both before continuing and possibly wasting a lot of my
volunteer time-budget.

@Eli: In many places in the code, there exist in-line documentation that
would be appropriate as a doc-string; however, those cases are mostly
internal functions of the form `cua--foo', so the question arose for me:
is there emacs policy NOT to produce doc-strings for such functions.
Personally, it's more convenient to my work-flow to be able to use ivy
to get a pop-up docstring for thing-at-point than to open either open a
buffer (only to have to immediately kill it) or ping-pong among places
in a single buffer. So my vote and inclination is make the doc-strings,
but policy is policy.

@Kim & @ELi: My initial notes and patch file are attached, for feedback
if I got anything wrong, and for approval of the proposed changes:

1. The docstring issue, until I realized I should ask.

2. @Kim: At the end of the first diff block, I noted an issue about the
  `cua--last-killed-rectangle' data structure. Could you set me right
   about it?

3. I noticed that `M-m' was bound to `cua-copy-rectangle-as-text'
   instead of `back-to-indentation', so I took the liberty of writing a
   function `cua-resize-rectangle-back-to-indentation' and binding it to
   `M-m', which is what most users would expect. If this approved, to
   what should be bound `cua-copy-rectangle-as-text'

4. Function `cua-resize-rectangle-bot' had a bug in that it always
   placed point at the actual (point-max) even though the rectangle
   corner would not be there. This would occur when (point-max) was at a
   column number smaller than the left edge of the rectangle. The patch
   file includes the fix.

5. Two commonly used navigation functions, normally bound to `C-a' and
   `C-e' were not remapped. (DONE)

6. The help message is remapped from `C-?' to `M-?' for the sanity of
   people like me who use emacs-nox and can only perform a `C-?' by
   typing `C-x @ c ?'.

7. The current keybindings are made using an old method of keystroke
   definition that I find a bit scary. Is it OK / desirable to change
   the method uniformly to use `kbd'?

First slow steps.

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