RunPager is weird and confusing in that it replaces what stdout *is*
depending on environmental conditions. this has not caused problems,
but it's easy to imagine situations in which it would (eg if the stl
decided to capture the stdout fd by duplicating it). using a wrapper
for this also makes clear *what* actually goes into the pager; while
the previous contract was semi-reasonable it was also very implicit,
and with the proliferation of functions we had that printed directly
to stdout it would have been easy to send wrong output to the pager.
using a wrapper also makes process management much easier because we
do not have to rely on destructors to always produce correct output.
Change-Id: Ifd3760940af1ec719fe856158c913cbb9a5bf270
eldritch horrors
a7bc1be03f