- This now logs the exact indexes that are getting removed so there is
  no more confusion.

- Fix #4075

The operator regressed in MongoDB 2.6 and higher and simply does not
work when used in conjunction with embedded documents more than one
level deep. This removes our use of it and replaces it with the common
index positions.

- Fix #4033

- Fix #3991
- Close #3992

- Fixes #3764

- Fixes #3104

- Fixes #4077

Fixes #4030

- Fix #4052

- Fixes #3868

Fixes #3874

- Fix #3811

- Fix #4005

- Ex: Band.find({ '$oid' => "918736281836271738dty23g" })

Closes #3963
Closes #3800

Fixes #3768

Force to use '_id' on method only and don't permit to remove '_id' with
method without.

Fixes #3740

 * Support for contexts in prepare_insert & prepare_update
 * Appropriate tests

database on store_in

There was a bug when combining #store_in and #with methods that the
session was not respecting the right database name.

[fixes #3722]

[fixes #3934]