swarm: plan bee for content storage and distribution on web3

This change imports the Swarm protocol codebase. Compared to the 'swarm'
branch, a few mostly cosmetic changes had to be made:

* The various redundant log message prefixes are gone.
* All files now have LGPLv3 license headers.
* Minor code changes were needed to please go vet and make the tests
  pass on Windows.
* Further changes were required to adapt to the go-ethereum develop
  branch and its new Go APIs.

Some code has not (yet) been brought over:

* swarm/cmd/bzzhash: will reappear as cmd/bzzhash later
* swarm/cmd/bzzup.sh: will be reimplemented in cmd/bzzup
* swarm/cmd/makegenesis: will reappear somehow
* swarm/examples/album: will move to a separate repository
* swarm/examples/filemanager: ditto
* swarm/examples/files: will not be merged
* swarm/test/*: will not be merged
* swarm/services/swear: will reappear as contracts/swear when needed

swarm/api/storage_test.go

@@ -0,0 +1,49 @@
+// Copyright 2016 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package api
+
+import (
+	"testing"
+)
+
+func testStorage(t *testing.T, f func(*Storage)) {
+	testApi(t, func(api *Api) {
+		f(NewStorage(api))
+	})
+}
+
+func TestStoragePutGet(t *testing.T) {
+	testStorage(t, func(api *Storage) {
+		content := "hello"
+		exp := expResponse(content, "text/plain", 0)
+		// exp := expResponse([]byte(content), "text/plain", 0)
+		bzzhash, err := api.Put(content, exp.MimeType)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		// to check put against the Api#Get
+		resp0 := testGet(t, api.api, bzzhash)
+		checkResponse(t, resp0, exp)
+
+		// check storage#Get
+		resp, err := api.Get(bzzhash)
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		checkResponse(t, &testResponse{nil, resp}, exp)
+	})
+}