Ability to get notUnique error from index not added by this package

To delete.

The question is logged here: aldeed/meteor-collection2-core#7

[aldeed]

I think this was because of the problem with the mongo errors that they don't tell you discreetly what field the error was for. So we do string parsing to figure out, but we can only do that reliably for indexes created by this package. So if you happened to create the same index already before this package tries to create it, then we can't name it properly so we can't parse it properly.

I'm not sure if more recent versions of Mongo might have added the property name to the error message. That would solve this.

[maxpdx]

@aldeed, any updates?