ClassManifest->ClassTag in lift-json-ext.
erasure->runtimeClass in lift-json-ext.
Import existentials as needed in lift-json-scalaz.
Import existentials as needed in lift-json-scalaz7.
Merge branch 'deprecator-exterminator' into json-and-the-argonauts
Merge pull request #1541 from lift/json-and-the-argonauts

JSON and the Argonauts: Fix src warnings in lift-json-ext, lift-json-scalaz, and lift-json-scalaz7