More work on the CMake build.

* CMakeLists.txt: Adjust for the changes listed below.
* build/SerfVersion.cmake: Renamed from build/version.cmake.
* build/SerfChecks.cmake: Renamed from build/feature.cmake.
* build/APRCommon.cmake: New; common code for FindAPR and FindAPRUTIL.
* build/FindAPR.cmake: Renamed from build/FindApr.cmake.
   Expose version, extract common code, fix variable names, support APR 2.x.
* build/FindAPRUTIL.cmake: Renamed from build/FindApu.cmake.
   Other changes as for FindAPR.cmake.


git-svn-id: https://svn.apache.org/repos/asf/serf/trunk@1834227 13f79535-47bb-0310-9956-ffa450edef68
8 files changed