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##### SUMMARY
<!--- Explain the problem briefly below -->
The word "ERROR" in an IOS log message causes terminal to parse an error. IOS_command modules doesn't register stdout, only the one line of log output with the word "Error" as stderr. Task fails.
##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
I'm using ios_command module, however, I believe the ios terminal plugin has the regex to parse stderr.  ansible/lib/ansible/plugins/terminal/ios.py 
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
Using 2.7.7. Difficult to copy and paste due to locked down environment.
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
See above.
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
Ubuntu 16.04.6

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
Use ios_command module to show logs in buffer on the device. Register the output as a variable. Debug the contents of the variable. If a line of logs contains the word "ERROR", the task will fail and stdout will be empty.

Actual log lines that have triggered this:
%IPSEC-3-REPLAY_ERROR: IPSec SA recieves anti-replay error, DP Handle 549, src_addr x.x.x.x, dest_addr y.y.y.y, SPI...

ISAKMP-ERROR: (0):Failed to find peer index node to update peer_info_list

<!--- Paste example playbooks or commands between quotes below -->
```yaml
- tasks
  ios_command:
    commands: show logging
  register: logs
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
Lines of logs registered in variable.stdout.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
Variable has no stdout, only stderr. Stderr is only the one line of logs that contained the word "ERROR".
<!--- Paste verbatim command output between quotes -->
```paste below

```

command returns, the connection plugin will raise an exception and
        close.
    default: 30
    ini:
      - section: persistent_connection
        key: command_timeout
    env:
      - name: ANSIBLE_PERSISTENT_COMMAND_TIMEOUT
    vars:
      - name: ansible_command_timeout
  persistent_buffer_read_timeout:
    type: float
    description:
      - Configures, in seconds, the amount of time to wait for the data to be read
        from Paramiko channel after the command prompt is matched. This timeout
        value ensures that command prompt matched is correct and there is no more data
        left to be received from remote host.
    default: 0.1
    ini:
      - section: persistent_connection
        key: buffer_read_timeout
    env:
      - name: ANSIBLE_PERSISTENT_BUFFER_READ_TIMEOUT
    vars:
      - name: ansible_buffer_read_timeout
  persistent_log_messages:
    type: boolean
    description:
      - This flag will enable logging the command executed and response received from
        target device in the ansible log file. For this option to work 'log_path' ansible