Here's my first stab at getting mod_auth_digest working under 2.0

Here's my first stab at getting mod_auth_digest working under 2.0

quick change summary:

 - moved the random byte generation into APR
   This patch adds ap_generate_random_bytes()
 - now uses ap_time_t
 - compiles and runs on linux
 - tested with amaya

still to do:

 - test win32 (This will have to be someone with a windows box :-)
   I think I did everything correctly.  APR_HAS_RANDOM should be defined
   on windows and there is a lib/apr/misc/win32/rand.c which is basically
   a copy of what mod_auth_digest used to use.
 - error handling cleanup
   Since there is not currently a usable ap_strerror it is commented out.
   win32 error handling is virtually non-existant.  I just don't know enough
   about win32 to touch this stuff.

Brian

Submitted by:	Brian Martin
Reviewed by:	Bill Stoddard (very quick review, moving in right direction)

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@84975 13f79535-47bb-0310-9956-ffa450edef68