As part of graph contraction, node renumbering leads to
in-place permuting of graph state, including boolean vector elements.
std::vector<bool> returns proxy objects when referencing individual
bits. To correctly swap bool elements using MSVC, we need to explicitly
apply std::vector<bool>::swap.
Making this change fixes osrm-contract on Windows.
We also correct failing tests and other undefined behaviours
(mainly iterator access outside boundaries) highlighted by MSVC.
Rename module partition to partitioner.
This cultivates naming used in existing modules like extractor,
customizer, etc. - noun vs verb (word partition is both though).
