MaxWriteBatchSize default is 1000 - ticket SERVER-12275

RUBY-676
bulk API spec v0.3 sync

RUBY-676
nRemoved replaces nDeleted, now in bulk API spec

RUBY-676
handle error code 11001 from server 2.4.9

RUBY-676
assert_match_document special cases for Regexp match, BSON::ObjectId, Range

RUBY-676
Set added to assert_match_document

RUBY-676
nModified from nDocsModified command or nUpdated operation response

RUBY-676
Merge branch '1.x-stable' into 1.x-stable-ruby-676
Merge branch 'gjmurakami-10gen-1.x-stable-ruby-676' into 1.x-stable