Merge pull request #2511 from Stebalien/local-api

Allow users to override the IPFS API address when fetching dependencies

Makefile

@@ -10,7 +10,7 @@ ldflags = "-X "github.com/ipfs/go-ipfs/repo/config".CurrentCommit=$(COMMIT)"
 MAKEFLAGS += --no-print-directory
 
 
-export IPFS_API = v04x.ipfs.io
+export IPFS_API ?= v04x.ipfs.io
 
 all: help