addGFontHtmlDependency
                        Use a font in Shiny or Markdown
font_family_exists      Check if font family exists.
fonts_cache_dir         manage font working directory
gfontHtmlDependency     'Google Font' HTML dependency
install_gfont_script    Shell command to install a font from 'Google
                        Fonts'
installed_gfonts        List installed 'Google Fonts'
liberationmonoHtmlDependency
                        'Liberation Mono' Font HTML dependency
liberationsansHtmlDependency
                        'Liberation Sans' Font HTML dependency
liberationserifHtmlDependency
                        'Liberation Serif' Font HTML dependency
m_str_extents           Compute string extents for a vector of string.
match_family            Find best family match with systemfonts
register_gfont          Register a 'Google Fonts'
register_liberationmono
                        Register font 'Liberation Mono'
register_liberationsans
                        Register font 'Liberation Sans'
register_liberationserif
                        Register font 'Liberation Serif'
str_extents             Compute string extents.
str_metrics             Get font metrics for a string.
strings_sizes           Compute strings sizes
sys_fonts               List fonts for 'systemfonts'.
version_freetype        Version numbers of C libraries
