fca 0.1.0

• Added a NEWS.md file to track changes to the package.
• First release of the fca package on CRAN.
• Perform various floating catchment area methods to calculate a spatial accessibility index (SPAI) for demand point data.
• The distance matrix used for weighting is normalized in a preprocessing step using common functions (gaussian, gravity, exponential or logistic).
• Improve test coverage.
• Bugfix: Avoid attempt to apply non-function in dist_normalize(..., imp_function="logistic").
• CRAN Feedback: Adjust moved URLs in README.Rmd and getting-started.Rmd vignette.