Writes a set of HTML files with tabbed navigation between them. Called by
plot_wham_output
if `out.type = 'html'` (default). Opens main file in
default browser. Modified from [`r4ss::SS_html`](https://github.com/r4ss/r4ss/blob/master/R/SS_html.R).
wham_html(dir.main = NULL, title = "WHAM Output", width = 500, openfile = TRUE)
directory to save html file (plot_wham_output
makes `.png` plot files in a `plots_png` subdirectory of `dir.main`).
Title for HTML page.
Width of plots (in pixels).
Automatically open index.html in default browser?
plot_wham_output
, `r4ss::SS_html()`