Adds repo version info to repo stat command

addresses ipfs#2571

License: MIT
Signed-off-by: Mike Pfister <pfista@gmail.com>

core/commands/repo.go

@@ -105,6 +105,7 @@ set of stored objects and print repo statistics. It outputs to stdout:
 NumObjects      int Number of objects in the local repo.
 RepoPath        string The path to the repo being currently used.
 RepoSize        int Size in bytes that the repo is currently taking.
+Version					string The repo version
 `,
 	},
 	Run: func(req cmds.Request, res cmds.Response) {
@@ -147,6 +148,7 @@ RepoSize        int Size in bytes that the repo is currently taking.
 				fmt.Fprintf(buf, "RepoSize \t %d\n", stat.RepoSize)
 			}
 			fmt.Fprintf(buf, "RepoPath \t %s\n", stat.RepoPath)
+			fmt.Fprintf(buf, "Version \t %s\n", stat.Version)
 
 			return buf, nil
 		},

core/corerepo/stat.go

@@ -10,6 +10,7 @@ type Stat struct {
 	NumObjects uint64
 	RepoSize   uint64 // size in bytes
 	RepoPath   string
+	Version    string
 }
 
 func RepoStat(n *core.IpfsNode, ctx context.Context) (*Stat, error) {
@@ -39,5 +40,6 @@ func RepoStat(n *core.IpfsNode, ctx context.Context) (*Stat, error) {
 		NumObjects: count,
 		RepoSize:   usage,
 		RepoPath:   path,
+		Version:    "fs-repo@" + fsrepo.RepoVersion,
 	}, nil
 }