BUMP 2.8.0-rc1
TOOLS-327 fix tests relying on --w to use --writeConcern
post 2.8.0-rc1
SERVER-15986 disable storage engine check
Revert "post 2.8.0-rc1"

This reverts commit dec3111d8bf4d6661be5b08f75d30a9fbe0c18ff.
Revert "Revert "post 2.8.0-rc1""

This reverts commit c8171e7f969519af8b87a43425ae291ee69a0191.