Add get_txns_spender to doc (#195)

* Add get_txns_spending to doc and first PR test

* Remove trailling space

* Update API doc

doc/API.v0.md

@@ -72,6 +72,59 @@ Proxy response:
   ]
 }
 ```
+### Get a list of txns from a watched label
+
+Returns the list of transactions not spend(txns) from watched label.
+
+```http
+GET http://cyphernode:8888/get_txns_by_watchlabel/Label
+```
+
+Proxy response:
+
+```json
+{
+  "label_txns": [
+    {
+      "label": "Label",
+      "address": "tb3qvsk9em20hgd76d489jyfdpy840vywk5qx9p5sg",
+      "txid": "d48171ecc2ea4310ee7a15d9f11d8410d6a658225152b0c27122de1999d87cb2",
+      "confirmations": "1",
+      "blockheight": "1817509",
+      "v_out": "0",
+      "amount": "2.545e-05",
+      "blockhash": "000000000000015df543042fa9179fe5e0823ef4e9a8cd52c9f26ce96b5935b1",
+      "blocktime": "1596496264",
+      "timereceived": "1596437271"
+    }
+  ]
+}
+```
+
+### Get a list of unused address from a watched label
+
+Returns the list all address not used from watched label.
+
+```http
+GET http://cyphernode:8888/get_unused_addresses_by_watchlabel/Label
+```
+
+Proxy response:
+
+```json
+
+{
+  "label_unused_addresses": [
+    {
+      "pub32_watch_id": "8",
+      "pub32_label": "Label",
+      "pub32": "xpub5VFKvW1pNiCCZqM4eB2qNmJKJnUEzcsWOPDnnR37jMZzMBof1YCiw3MnVPgyTY8RFiBMSPX3rf3M1zGckKdsLoNv64FBd8E1vTS2PzqEgSz",
+      "address_pub32_index": "0",
+      "address": "tb1qvqdit92g96dkch5soru8p3c6whtn2w82n85fj6"
+    }
+  ]
+}
+```
 
 ### Watch a Bitcoin xpub/ypub/zpub/tpub/upub/vpub extended public key (called by application)
 
@@ -576,6 +629,39 @@ GET http://cyphernode:8888/executecallbacks
 
 Proxy response: EMPTY
 
+### Get txns from spending wallet
+
+Calls listtransactions bitcoin RPC on the spending wallet.
+
+```http
+GET http://cyphernode:8888/get_txns_spending
+```
+
+Proxy response:
+
+```json
+{
+  "txns": [
+    {
+      "address": "tb1qfk6r46fj0u0we3c9lt0arl0dhqg2cry2sch7mf",
+      "category": "receive",
+      "amount": 0.00160052,
+      "label": "",
+      "vout": 0,
+      "confirmations": 21125,
+      "blockhash": "000000008c232ec9447e0cbcefdbd128a707c98189d4ab5036fdce3c313f0621",
+      "blockindex": 73,
+      "blocktime": 1595094603,
+      "txid": "dc598f96f50f6b1ab36b3172315e0fd928279dd0d909708b60af124c022e1e68",
+      "walletconflicts": [],
+      "time": 1595096613,
+      "timereceived": 1595216058,
+      "bip125-replaceable": "no"
+    }
+  ]
+}
+```
+
 ### Get spending wallet's balance (called by application)
 
 Calls getbalance RPC on the spending wallet.