Reorganize to go get will work

This makes almost no changes to source, but touches every almost file.

Also fixes error in gremlin test code.

graph/session.go

@@ -0,0 +1,45 @@
+// Copyright 2014 The Cayley Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package graph
+
+// Defines the graph session interface general to all query languages.
+
+type ParseResult int
+
+const (
+	Parsed ParseResult = iota
+	ParseMore
+	ParseFail
+)
+
+type Session interface {
+	// Return whether the string is a valid expression.
+	InputParses(string) (ParseResult, error)
+	ExecInput(string, chan interface{}, int)
+	ToText(interface{}) string
+	ToggleDebug()
+}
+
+type HttpSession interface {
+	// Return whether the string is a valid expression.
+	InputParses(string) (ParseResult, error)
+	// Runs the query and returns individual results on the channel.
+	ExecInput(string, chan interface{}, int)
+	GetQuery(string, chan map[string]interface{})
+	BuildJson(interface{})
+	GetJson() (interface{}, error)
+	ClearJson()
+	ToggleDebug()
+}