two spaces after sentence + other doc janitorial duties

[Thien-Thi Nguyen]

Normally, texinfo source should have two spaces after each sentence:

   Blah the first. Blah more.      ;; only one space, not cool
   Blah the first.  Blah more.     ;; two spaces, ok

I started locally modifying doc/ref/*.texi, when midway though discovered
api-undocumented.texi, which led me to doc/maint/docstring.el, which leads
me to believe that modifing doc/ref/*.texi is not so smart, since a future
update using docstring.el would overwrite them.  Better to make the changes
upstream (in libguile/*.c SCM_DEFINE forms, to be precise), no?

Further digging, i see one of the last docstring.el-using updates was:

  commit 3323ec063ccc87b210e6da04c57c625af270b230
  Author: Neil Jerram <address@hidden>
  Date:   Sun Dec 27 23:24:09 2009 +0000
  
      Automatic manual updates following libguile docstring changes
      
and since then there have been many other manual updates.  So, should i
interpret the six months since that update to mean that we are no longer
using a docstring.el-based system?  Am i missing something?

I suppose a shorter question would be: What do you all suggest for doing
"two spaces" and other doc cleanups -- which source is the true source?

Other changes i have in mind:

 - convert "..." to "@dots{}";
 - convert "i.e. FOO" to "i.e., FOO"
   (and likewise "i. e. FOO" and "e.g. FOO");
 - choose "Returns" or "Return" and use it everywhere;

Last related question: I realize that a subset of the doc/ref/*.texi do
not derive from docstring.el (for example vm.texi), so can be operated
on directly w/o qualms.  How about i collect changes to those files onto
branch ‘ttn/janitor-doc’ and simply post "rfc: SHA1"?  I can't imagine
huge diffs would be welcome on the list...

thi