Merge PIVX-Project#2774: add include_delegated to vRPCConvertParams

2334061 add include_delegated to vRPCConvertParams (PeterL73)

Pull request description:

  ## Issue being fixed PIVX-Project#2773
  Spending with ```sendmany``` and ```include_delegated``` parameter, results in ```JSON value is not a boolean as expected``` error
  ```
  ./pivx-cli sendmany "" "{\"<address>\":1}" 1 "" true
  error code: -1
  error message:
  JSON value is not a boolean as expected
  ```
  ```include_delegated``` is missing from vRPCConvertParams
  ## What was done?
  ```include_delegated``` was added to vRPCConvertParams
  ## How Has This Been Tested?
  ```
  ./pivx-cli sendmany "" "{\"<address>\":1}" 1 "" true
  <transaction hash>
  ```
  The transactions got added
  ## Checklist:
  <!--- Go over all the following points, and put an `x` in all the boxes that apply. -->
  - [x] I have performed a self-review of my own code
  - [x] I have performed a test of my own code

ACKs for top commit:
  Liquid369:
    uTACK 2334061
  DeanSparrow:
    ACK 2334061
  Fuzzbawls:
    ACK 2334061

Tree-SHA512: c2a676b0ab559c51298c84c1e297486ab256f51c78dc4d9ca15e356795e2080409625f37f7929dcd635cfe8b86303b67c665cf5bf3f1c9929b02a97202c1c3b7

src/rpc/client.cpp

@@ -140,6 +140,7 @@ static const CRPCConvertParam vRPCConvertParams[] = {
     { "rescanblockchain", 1, "stop_height"},
     { "sendmany", 1, "amounts" },
     { "sendmany", 2, "minconf" },
+    { "sendmany", 4, "include_delegated" },
     { "sendmany", 5, "subtract_fee_from" },
     { "sendrawtransaction", 1, "allowhighfees" },
     { "sendtoaddress", 1, "amount" },