dxFeed C API 6.1.0
- [DXFC-199] Fixed the IPF parsing in the PerformanceTest
- The minimal version of CMake changed to 3.0.0
- Build on CentOS switched to CentOS 7
- [DXFC-200] [Linux] Added ability to build a static library and samples
- Windows pthreads headers were removed from the project