RPC client (#42)

* Started RPC package to allow querying balances and sending raw transactions for sc's

* integrate invoke cmd in cli

* bumped version

* added sendrawtransaction to the rpc client.

pkg/rpc/types.go

@@ -0,0 +1,72 @@
+package rpc
+
+type InvokeScriptResponse struct {
+	responseHeader
+	Result *InvokeResult
+}
+
+// InvokeResult represents the outcome of a script that is
+// executed by the NEO VM.
+type InvokeResult struct {
+	State       string `json:"state"`
+	GasConsumed string `json:"gas_consumed"`
+	Stack       []*StackParam
+}
+
+// StackParam respresent a stack parameter.
+type StackParam struct {
+	Type  string `json:"type"`
+	Value string `json:"value"`
+}
+
+// AccountStateResponse holds the getaccountstate response.
+type AccountStateResponse struct {
+	responseHeader
+	Result *Account `json:"result"`
+}
+
+// Account respresents details about a NEO account.
+type Account struct {
+	Version    int    `json:"version"`
+	ScriptHash string `json:"script_hash"`
+	Frozen     bool
+	// TODO: need to check this field out.
+	Votes    []interface{}
+	Balances []*Balance
+}
+
+// Balance respresents details about a NEO account balance.
+type Balance struct {
+	Asset string `json:"asset"`
+	Value string `json:"value"`
+}
+
+type params struct {
+	values []interface{}
+}
+
+func newParams(vals ...interface{}) params {
+	p := params{}
+	p.values = make([]interface{}, len(vals))
+	for i := 0; i < len(p.values); i++ {
+		p.values[i] = vals[i]
+	}
+	return p
+}
+
+type request struct {
+	JSONRPC string        `json:"jsonrpc"`
+	Method  string        `json:"method"`
+	Params  []interface{} `json:"params"`
+	ID      int           `json:"id"`
+}
+
+type responseHeader struct {
+	ID      int    `json:"id"`
+	JSONRPC string `json:"jsonrpc"`
+}
+
+type response struct {
+	responseHeader
+	Result interface{} `json:"result"`
+}