Merge branch 'js/stop-exporting-bogus-columns' into seen

Merge branch 'js/stop-exporting-bogus-columns' into seen

When we cannot figure out how wide the terminal is, we use a
fallback value of 80 ourselves (which cannot be avoided), but when
we run the pager, we export it in COLUMNS, which forces the pager
to use the hardcoded value, even when the pager is perfectly
capable to figure it out itself.  Stop exporting COLUMNS
only when building on Windows to work around this issue.

* js/stop-exporting-bogus-columns:
  pager: do not unnecessarily set COLUMNS on Windows