Cityseer

- Addresses edge cases (`np.inf` vs `-np.inf`) in the conversion of betas <-> distances.
- Adds a progress bar for `numba` functions

Breaking Changes
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To address semantics around the use of the term "gravity":
- Renames centrality 'gravity' key to `gravity_index`. The latter matches usage of the term in urban network centrality literature, though it must be emphasised that this is actually a spatial impedance index, not to be confused with gravity in the scientific sense, or gravity modelling in the transportation modelling sense.
- Renames `betweenness_gravity` to `betweenness_decay`.

- Renames and moves mock_osm_graph to graphs.nX_from_osm
- Adds guide for graph cleanup based on OSM data

- Adds image examples for graph consolidation methods.
- Updates dependency for vuepress theme (new modal images)
- Adds-back highest-degree method for spatial node consolidation in order to better preserve graph topology. (Not used for parallel consolidation method.)

Fixes bug which returned point geom instead of point id from _find_parallel() function.

Newly split points will now be merged as intended.

Added alternate OSM data sample and fixed potential division by zero situation.

Splitting out duplicitous code. Fixed missing edge params re: consolidation step.