Fix build issues on CentOS Hi. I had problems compiling modwaklog using CentOS and the latest openafs from git. I managed to work out generally-useful solutions to the problems, so I thought I'd send this patch on. 1. I added a configuration option to tell it where to find the apr headers. 2. The afs headers to include have changed. It was complaining that afs_int32 was undefined. I now include <afs/param.h>, which is apparently the accepted thing to do for afs programs. 3. When my build was completed, I found the .so file not in the main directory, but in .libs/mod_waklog.so. I updated the documentation to say to look for it there. I attached a patch that fixed these problems for me. Thanks. --Ryan