Documentation Update + Correcting Typo

[Scrubzie]

Add doc strings for these

• ~distance_factory.py~
• ~solver_factory.py~
• ~vehicle_clusterer_factory.py~
• ~app.py~
• mapbox_distance_finder.py
• ~tsp_formulation.py~
• ~brute_force_solver.py~

Update ReadMes

• ~route_solver's README~
• distance_matrix's README
• route_optimisation README

Correct Typo

• ~time_times in tsp_formulation.py~

[Sonny6155]

Outdated. Remaining work will be covered by #98.