code: public Integer getAccountsCount(final QueryParams params) {
          FluentCaseInsensitiveStringsMap map = doHEAD(Accounts.ACCOUNTS_RESOURCE, params);
          return Integer.parseInt(map.getFirstValue(X_RECORDS_HEADER_NAME));
      }
docs: Get number of Accounts matching the query params
  
  @param params {@link QueryParams}
  @return Integer on success, null otherwise