fixed issue with findOneAndUpdate not returning null on upserts

if new=false, upserts were not appropriately returning null. fixes #1533
Merge pull request #1569 from 10gen-interns/findAndUpdate-fix

fixed issue with findOneAndUpdate not returning null on upserts
docs; note about toObject behavior during save()
Added geoNear support for mongoose

geoNear & associated tests
remove some nesting
remove unused variable

closes #1570
bump driver to 1.3.11
update history
tests; ensure geo index has been created first
tests; fix race in geo search
Initial work on integrating mquery

basic operations seem to work, have not done unit testing though.
More complicated stuff such as mapreduce have not been re-impemented
also, need to reorganized the mongoosequery.js code
all model.querying.test.js unit tests are passing now

there were a couple bug fixes in the actual tests, as well as updates to
MongooseQuery from Query. Most bug fixes were in the MongoosQuery and
Model methods though.
more bug fixes for update()
all of the model.update.test.js tests are passing now
forgot to remove a .only() in the tests
more tests passing, still a few more to fix
re-wrote _findAndModify and updated mquery version

had to stop using mquery's _findAndModify due to casting issues
updated exec to return a promise

wrapped mquery's exec() to make sure it returns a promise
using the wrong options in findOne()

needed to be using the _mongooseOptions, not the mquery options
removed the namescoped tests - feature is being depreciated