starschemar 1.2.0

New data sets to enrich dimensions: [ft_london_boroughs], [ft_usa_states] and [ft_usa_city_county].
The data set [ms_mrs] has been defined according to the result obtained in the vignette, so it can be used by other packages.
New function to get missing instances to enrich a dimension: [enrich_dimension_import_test()].
New functions to get star schema names and a star schema in a constellation: [get_star_schema_names] and [get_star_schema].
Improve the structure and content of the vignette.

starschemar 1.1.0

New dimension enrichment features: [enrich_dimension_export()] and [enrich_dimension_import()].
New functions to filter facts and purge dimensions (delete unnecessary data): [filter_fact_rows()] and [purge_dimensions()].
New query definition functions on the exported multistar format: [dimensional_query()], [select_fact()], [select_dimension()], [filter_dimension()] and [run_query()].
New functions to rename dimensions, attributes, facts and measures in a star schema: [rename_dimension()], [get_dimension_attribute_names()], [rename_dimension_attributes()], [rename_fact()], [get_measure_names()] and [rename_measures()].
New function to export a multistar (possibly obtained as a result of a query) as a flat table: [multistar_as_flat_table()].
New data available to develop additional examples: [ft_datagov_uk].