Collection manager not parsing errors correctly

There are a number of errors that I think have changed their error message response from the server and therefore the errors are not being parsed correctly.

Here's a list of the current (7.0.0-3435 internal beta) error responses:

Scope already exists:
{"errors":{"_":"Scope with name \"2d33a596-8\" already exists"}}

Collection already exists:
{"errors":{"_":"Collection with name \"b185d9f9-0\" in scope \"7df92294-3\" already exists"}}

Scope not found:
{"errors":{"_":"Unknown error {error,{scope_not_found,\"foobar\"}}"}}

Collection not found
{"errors":{"_":"Unknown error {error,{collection_not_found,\"a9e4f276-3\",\"1141f1d0-b\"}}"}}

There are a number of test failures related to this: http://sdk.jenkins.couchbase.com/view/Nightly/job/jvm/job/jvm-clients/job/couchbase-jvm-clients-scipted-build-pipeline/521/testReport/com.couchbase.client.java.manager.collection/CollectionManagerIntegrationTest/