camput: add debug mechanism CAMLI_NO_FILE_DUP_SEARCH to disable fileMapFromDuplicate

Change-Id: I1772ed69cccd4245e660887e257da2ab30bd59e4
schema: make serverHasBlob just use blobserver.StatBlob

Change-Id: I3012763660c9ed87eb48b2d95b8265c3c77f32df
client: batch and split stat requests

Change-Id: I40e64cc2de58040bb67c6560a64ba108c421b18d
client: remove debug logs

Change-Id: Iba67ff3daceb17766d17337d8b84e58ed3e96ab7
schema: remove FileWriter's serial byte/file schema uploads after chunks are uploaded

Change-Id: I1c3a9c496ce168cc8b6d087ef1a0de99cac22127