NODE-158 fix statistical strategy
Added tests for w:0 and some small fixes for merging results
Merge remote-tracking branch 'val/statistics-strategy' into 1.4
Fixes for write concerns correctly propegated through gridfs
Handle error on documents to big
Fixed integra version
force build
Minor fixed in version checking and tests
Updated version for release
Changed default chunk size to be 255 * 1024 to optimize on power of 2 allocation as default strategy in 2.6