help: attempt to clarify that pager usage is not output length based This may be too subtle of a change to get the point across, but when I first read the original text, I thought maybe the pager would only be invoked if writing more than a screenful. The distinction between this and a pager that simply exits after printing less than a screenful is important on Windows, given the inability of `more` to color output.

--- a/mercurial/help/pager.txt	Wed May 03 21:58:11 2017 -0400
+++ b/mercurial/help/pager.txt	Wed May 03 22:05:23 2017 -0400
@@ -1,4 +1,4 @@
-Some Mercurial commands produce a lot of output, and Mercurial will
+Some Mercurial commands can produce a lot of output, and Mercurial will
 attempt to use a pager to make those commands more pleasant.
 
 To set the pager that should be used, set the application variable::