* feat: Add unit test for two level customization
issues: #49
* feat: Add class for statistic set and related unit test
issue: #49
* Initial commit of cell_update_record with unit tests.
* feat: Initial commit of cell_update_record with unit tests.
issue: #49
* Refactor code.
* Refactor code.
issue: #49
* Integrate logic with customization
issue: #49
* fix: adjust comments
issue: #49
* feat: add flag of incremental, will load previous metrix table if set to true
issues: #49
* fix: compilation in docker.
issues: #49
* fix: fix crash issue and add protection code
issues: #49
* Fix: Update code based on pull request's comments
issue: #49
* fix: Remove util/concurrent_set, directly define set in updater.hpp
issue: #49
* fix: Passing shared_ptr by reference.
Rename module partition to partitioner.
This cultivates naming used in existing modules like extractor,
customizer, etc. - noun vs verb (word partition is both though).
There is no possibility until multiple-weights are implemented
to break tie in the contraction and the direct shortest path plugin
as duration is not computed during contraction.
This must be fixed after multiple-weights implementation
by using `std::tie(weight, duration)` pairs everywhere.
