path: ignore prefix /ipfs/

gc closed conns

Fix test_docker Makefile target and rename it test_3node

```
2015/01/07 21:57:16 COPY has been deprecated. Please use ADD instead
```

Thanks @inconshreveable

The dockertest/ directory has been moved into test/ and
it has been renamed 3nodetest/ in commit 28cf220d
(dockertest -> test/3nodetest).

License: MIT
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>

merkledag traversal

test reorg

kept bin in place

ipfs object learned stat

'ipfs object stat' is a plumbing command to print DAG
node statistics. <key> is a base58 encoded multihash.
It outputs to stdout:

  NumLinks        int number of links in link table
  BlockSize       int size of the raw, encoded data
  LinksSize       int size of the links segment
  DataSize        int size of the data segment
  CumulativeSize  int cumulative size of object and references

ipfs block stat cmd

Ignore debug profile files in .gitignore

Command channel output 

core/commands: Don't use pointers for Type field