DemographicTable 0.1.6

Add exception handling for Fisher’s exact test # DemographicTable 0.1.5 Add xtable.DemographicTable for LaTeX output # DemographicTable 0.1.4 Bug fix. # DemographicTable 0.1.3 Accommodate package flextable update on 2022-06-01 # DemographicTable 0.1.2 Bug fix. # DemographicTable 0.1.1 Bug fix. # DemographicTable 0.1.0 First release.