Doxygen (#58)

* purge deprecated

* Doxyfile

* fix typo

Author: koide3

README.md

@@ -425,7 +425,7 @@ Processing speed comparison between small_gicp and Open3D ([youtube]((https://yo
 
 - Single-thread `small_gicp::GICP` is about **2.4x and 1.9x faster** than `pcl::GICP` and `fast_gicp::GICP`, respectively.
 - `small_gicp::(GICP|VGICP)` shows a better multi-thread scalability compared to `fast_gicp::(GICP|VGICP)`.
-- `small_gicp::GICP` parallelized with [TBB flow graph](src/odometry_benchmark_small_gicp_tbb_flow.cpp) shows an excellent scalability to many-threads situations (**~128 threads**) but with latency degradation.
+- `small_gicp::GICP` parallelized with [TBB flow graph](src/benchmark/odometry_benchmark_small_gicp_tbb_flow.cpp) shows an excellent scalability to many-threads situations (**~128 threads**) but with latency degradation.
 - Outputs of `small_gicp::GICP` are almost identical to those of `fast_gicp::GICP`.
 
 ![odometry_time](docs/assets/odometry_time.png)