Merge pull request #770 from jbenet/pkg-docs

document some packages

cmd/ipfs/main.go

+// cmd/ipfs implements the primary CLI binary for ipfs
 package main
 
 import (

core/commands/add.go

@@ -57,6 +57,7 @@ remains to be implemented.
 		cmds.BoolOption("quiet", "q", "Write minimal output"),
 		cmds.BoolOption(progressOptionName, "p", "Stream progress data"),
 		cmds.BoolOption(wrapOptionName, "w", "Wrap files with a directory object"),
+		cmds.BoolOption("t", "trickle", "Use trickle-dag format for dag generation"),
 	},
 	PreRun: func(req cmds.Request) error {
 		if quiet, _, _ := req.Option("quiet").Bool(); quiet {

core/core.go

+// package core implements the IpfsNode object and methods for constructing
+// and properly setting it up.
 package core
 
 import (

exchange/bitswap/decision/engine.go

+// package decision implements the decision engine for the bitswap service.
 package decision
 
 import (

exchange/bitswap/wantlist/wantlist.go

+// package wantlist implements an object for bitswap that contains the keys
+// that a given peer wants.
 package wantlist
 
 import (

namesys/interface.go

+// package namesys implements various functionality for the ipns naming system.
 package namesys
 
 import (