SERVER-13091 fix RSSync cpp unit test
extra debugging to help fix rollback4.js
SERVER-13084,SERVER-13632,SERVER-13634 Remove DiskLoc methods hitting disk
SERVER-13715 plan subqueries on construction of a SubplanRunner

This enforces the error behavior expected by aggregation.
SERVER-13777 migrated ranges waiting for deletion do not report cursors still open
SERVER-13641: add methods to transaction to check if an op is killed
SERVER-13639: small cleaning of Extent header
Merge remote-tracking branch 'upstream/master'