bug#10650: view-mode inconsistencies wrt special mode-class

[Juri Linkov]

> This came up before in some long thread:
> http://debbugs.gnu.org/cgi/bugreport.cgi?bug=4896#153
>
>   I think the right solution should be to let the major mode say
>   explicitly that it is mutually-exclusive with view-mode.

Another thread worth to read is:
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=8615

> It would seem better to have some new explicit property for this, rather
> than stealing special mode-class.

Or a new user option defined in view.el with a list of modes where
view-mode should not be activated; with the default value like
`(image-mode archive-mode tar-mode)'.