* util/build_verion.cc.in: add this file, so cmake and make can share the
template file for generating util/build_version.cc.
* CMakeLists.txt: also, cmake v2.8.11 does not support file(GENERATE ...),
so we are using configure_file() for creating build_version.cc.
* Makefile: use util/build_verion.cc.in for creating build_version.cc.
Signed-off-by: Kefu Chai <tchaikov@gmail.com>