[server] Pagination for LDAP user list.
autogen - Use env(1) to call bash.
configure.ac - Use AC_CANONICAL_HOST for OS checking.
[dragonfly] - Don't try to use libuuid for DragonFly BSD
configure.ac - Do not assume everyone not WIN32 is Linux or MAC
autogen.sh - Change $TERMINAL_PROGRAM check.

This way the script can be run by Bourne Shell.
Do not call sed directly, use ${SED} instead.

autotools will determine which sed program to use, hence call
${SED} instead of directly calling sed binary.
configure.ac - Change the library checking logic.
[dragonfly] - Create a function to generate UUIDs.

Also include specific libevent2 includes instead of using include-all
headers.
Include specific libevent2 header files instead of using include-all
headers.

This fixes compilation in DragonFly when using libevent2 from Dports.