[drupal-docs] Documenting PHP requirements

[Robert Douglass]

Innocent question:

How accurate/complete are the OPTIONAL REQUIREMENTS in the install 
instructions with regards to PHP extensions?

OPTIONAL REQUIREMENTS
---------------------
- To use XML-based services such as the Blogger API, Jabber, RSS
   syndication, you will need PHP's XML extension. This extension is
   enabled by default in standard PHP4 installations.

What about mentioning GD and Mbstring? Are they ever *missing* from PHP4 
(4.3.3 or greater) or PHP5? Are there other extensions that are really 
useful and that we should mention? What extensions do *you* have 
compiled in or turned on?

cheers

Robert