cmake: update timestamp status
authorAlexander Alekhin <alexander.alekhin@intel.com>
Wed, 13 Dec 2017 12:16:03 +0000 (15:16 +0300)
committerAlexander Alekhin <alexander.alekhin@intel.com>
Wed, 13 Dec 2017 12:31:36 +0000 (15:31 +0300)
commit3e45795232c34f45769a90c2d03482947af4084d
tree882204614a1824ca3dd6a5ecb909929cb5a7f910
parent84ee4d701ac592ff21f00edcf9583035e54d0b28
cmake: update timestamp status

- avoid unnecessary rebuilding of OpenCV libraries
- use timestamp of the first launch of CMake
- to return to previous behavior use `-UOPENCV_TIMESTAMP` CMake option
CMakeLists.txt