Interesting intangible hack

[Richard Stallman]

I wrote some code that prevents point from stopping
after an invisible, intangible character.  I hope
this will make the behavior of invisible, intangible text
more natural, but code which knows about such text
may need changes.  I made changes in line-move to handle this
(and also cleaned it up an awful lot).

I am very interested in getting comments on this feature,
because it is easy to imagine that it might have problems
that I did not notice.