tests/test-gendoc-ru.t

phabricator: rework phabread to reduce memory usage and round-trips

This patch reworked phabread a bit so it fetches the lightweight
"Differential Revision" metadata for a stack first. Then read other data.

This allows the code to:

  a) send 1 request to get all `hg:meta` data instead of N requests
  b) patches are read in desired order, no need to buffer the output

"b)" reduces the memory usage from O(N^2) to O(N) since we no longer keep
old patch contents in memory.

The above `N` means the number of patches in the stack.

#require docutils gettext

  $ $TESTDIR/check-gendoc ru
  checking for parse errors