This function should generally not be needed, except if graph
structure has been directly modified other than through dodgr functions;
for example by modifying edge weights or distances. Graphs are cached based
on the vector of edge IDs, so manual changes to any other attributes will not
necessarily be translated into changes in dodgr output unless the cached
versions are cleared using this function. See
https://github.com/UrbanAnalyst/dodgr/wiki/Caching-of-streetnets-and-contracted-graphs
for details of caching process.
See also
Other cache:
dodgr_cache_off(),
dodgr_cache_on(),
dodgr_load_streetnet(),
dodgr_save_streetnet()