Subject: Only bank-bank transactions in BRS

Description:
1. Bank Reconciliation Statement will have only bank-bank transactions.
   Reason is,

Following are the situations where contra entries arises
1. Cash to bank
2. bank to cash
3. bank to bank
4. ATM transactions

In situations 1, 2 & 4, there will be no difference between the date of
deposit/withdrawals in bank/company records.  So the date of entry would
be the date of deposit/withdrawal, so there is no difference between the
balances of Books and Bank stmt.  Hence these transactions shall not appear in BRS.

In Situation 3 due to online remittance / RTGS transfers time delay will
be 2-5 days due to bank operations.  This transaction will appear in BRS
like any other cheque transactions.  Hence this transaction forms part of BRS.

2. Added new rpc_function getSubGroupCodeByAccountName in rpc_groups.py

3. Relevant modifications in function getLedger, getReconLedger and updateBankRecon
   in rpc_reports.py