Sync Gateway sync function and Underscore.js

At least as of Sync Gateway 2.1, there is an ability to use two libraries such as underscore.js and builtin JSON.stringify.
Maybe this is on purpose that it isn't mentioned on the documentation, but it could make life extremely easier for who is developing the sync function.

it make the use of _.isEqual, _.omit, _.isUndefined and more , accessible.