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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
The [PSRP documentation](https://docs.ansible.com/ansible/latest/plugins/connection/psrp.html) mentions `ansible_psrp_connection_backoff` but this seems to be incorrect. The code appears to refer to `ansible_psrp_reconnection_backoff` instead (`reconnection` vs `connection`).
<!--- HINT: Did you know the documentation has an "Edit on GitHub" link on every page ? -->

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
PSRP
lib/ansible/plugins/connection/psrp.py

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python2.7/dist-packages/ansible-2.8.0.dev0-py2.7.egg/ansible
  executable location = /usr/local/bin/ansible
  python version = 2.7.15rc1 (default, Nov 12 2018, 14:31:15) [GCC 7.3.0]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
None
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. OS version, browser, etc. -->
Linux, Ubuntu 18.04.2 LTS

##### ADDITIONAL INFORMATION
<!--- Describe how this improves the documentation, e.g. before/after situation or screenshots -->
None.
<!--- HINT: You can paste gist.github.com links for larger files -->
stdout_list += self.host.ui.stdout
        stdout = u"\r\n".join(stdout_list)
        stderr_list = []
        for error in pipeline.streams.error:
            
            
            command_name = "%s : " % error.command_name if error.command_name else ''
            position = "%s\r\n" % error.invocation_position_message if error.invocation_position_message else ''
            error_msg = "%s%s\r\n%s" \
                        "    + CategoryInfo          : %s\r\n" \
                        "    + FullyQualifiedErrorId : %s" \
                        % (command_name, str(error), position,
                           error.message, error.fq_error)
            stacktrace = error.script_stacktrace
            if self._play_context.verbosity >= 3 and stacktrace is not None:
                error_msg += "\r\nStackTrace:\r\n%s" % stacktrace
            stderr_list.append(error_msg)
        if len(self.host.ui.stderr) > 0:
            stderr_list += self.host.ui.stderr
        stderr = u"\r\n".join([to_text(o) for o in stderr_list])
        display.vvvvv("PSRP RC: %d" % rc, host=self._psrp_host)
        display.vvvvv("PSRP STDOUT: %s" % stdout, host=self._psrp_host)
        display.vvvvv("PSRP STDERR: %s" % stderr, host=self._psrp_host)
        
        
        self.host.rc = 0
        self.host.ui.stdout = []
        self.host.ui.stderr = []
        return rc, to_bytes(stdout, encoding='utf-8'), to_bytes(stderr, encoding='utf-8')