Remove long-dead deprecation documentation

[Sandra Loosemore]

On 03/21/2018 05:11 AM, Nathan Sidwell wrote:
> Sandra,
> this removes the now-deleted deprecated features. AFAICT these have been 
> gone for a long time -- 2008 is the most recent changelog entry -- so no 
> need to put it in any release notes.
> 
> ok?

Yes, this is fine.  At some point we might want to do more cleanup here, 
but getting rid of obsolete stuff means there's less left to clean up.  :-)

-Sandra