Return resultfrom insertflat() to allow chaining of operations

--HG--
extra : rebase_source : d16f1f0e4255d3f898294f35d8962944f51d02c8
Move path.normalize() to native code for performance

--HG--
extra : rebase_source : 32da0058d5ae7d71de545f265876aa66e077927b