bundle2: make sure standard stream are binary Python on Windows apparently use encoded stream by default. We use the same trick than elsewhere in the code to make them binary. This should fix the current buildbot failure on windows.

revset-benchmark: add max(::(tip~20) - obsolete()) This revset is used in evolve. The new revset lazyness should make it all faster but in practice it is significantly slower. Below is a timing for this entry on my Mercurial repo. 2.9.2) ! wall 0.034598 comb 0.040000 user 0.040000 sys 0.000000 (best of 100) 3.0+@) ! wall 0.062268 comb 0.060000 user 0.060000 sys 0.000000 (best of 100) The ~20 have been taken arbitrary.