<!--- Verify first that your issue is not already reported on GitHub -->
<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Explain the problem briefly below -->
anisble-doc is failing on below line
https://github.com/dynatrace-innovationlab/ansible_dynatrace_problem_comment/blob/master/library/dynatrace_comment.py#L47
##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
ansible-doc
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below

```

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

```

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


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
ansible-doc changes the line to something like below
u'Source where the comment originates from (default': u'Ansible)'
The above is not a valid python string and hence it throws an exception
<!--- Paste example playbooks or commands between quotes below -->
```yaml

```

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

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
No exception  should be thrown, instead ansible-doc should fail the test

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
ansible-doc -t module dynatrace_innovationlab.dynatrace_collection.dynatrace_comment dynatrace_innovationlab.dynatrace_collection.dynatrace_deployment -vvv

<!--- Paste verbatim command output between quotes -->
```paste below
Traceback (most recent call last):
  File "/home/abehl/work/src/anshul_ansible/ansible/bin/ansible-doc", line 111, in <module>
    exit_code = cli.run()
  File "/home/abehl/work/src/anshul_ansible/ansible/lib/ansible/cli/doc.py", line 198, in run
    textret = DocCLI.format_plugin_doc(plugin, loader, plugin_type, search_paths)
  File "/home/abehl/work/src/anshul_ansible/ansible/lib/ansible/cli/doc.py", line 309, in format_plugin_doc
    text += DocCLI.get_man_text(doc)
  File "/home/abehl/work/src/anshul_ansible/ansible/lib/ansible/cli/doc.py", line 598, in get_man_text
    DocCLI.add_fields(text, doc.pop('options'), limit, opt_indent)
  File "/home/abehl/work/src/anshul_ansible/ansible/lib/ansible/cli/doc.py", line 476, in add_fields
    text.append(textwrap.fill(DocCLI.tty_ify(entry), limit, initial_indent=opt_indent, subsequent_indent=opt_indent))
  File "/home/abehl/work/src/anshul_ansible/ansible/lib/ansible/cli/__init__.py", line 426, in tty_ify
    t = cls._ITALIC.sub("`" + r"\1" + "'", text)    # I(word) => `word'
TypeError: expected string or buffer
```

super(DocCLI, self).__init__(args)
        self.plugin_list = set()
    def init_parser(self):
        super(DocCLI, self).init_parser(
            desc="plugin documentation tool",
            epilog="See man pages for Ansible CLI options or website for tutorials https://docs.ansible.com"
        )
        opt_help.add_module_options(self.parser)
        opt_help.add_basedir_options(self.parser)
        self.parser.add_argument('args', nargs='*', help='Plugin', metavar='plugin')
        self.parser.add_argument("-t", "--type", action="store", default='module', dest='type',
                                 help='Choose which plugin type (defaults to "module"). '
                                      'Available plugin types are : {0}'.format(C.DOCUMENTABLE_PLUGINS),
                                 choices=C.DOCUMENTABLE_PLUGINS)
        self.parser.add_argument("-j", "--json", action="store_true", default=False, dest='json_format',
                                 help='Change output into json format.')
        exclusive = self.parser.add_mutually_exclusive_group()
        exclusive.add_argument("-F", "--list_files", action="store_true", default=False, dest="list_files",
                               help='Show plugin names and their source files without summaries (implies --list)')
        exclusive.add_argument("-l", "--list", action="store_true", default=False, dest='list_dir',
                               help='List available plugins')
        exclusive.add_argument("-s", "--snippet", action="store_true", default=False, dest='show_snippet',
                               help='Show playbook snippet for specified plugin(s)')
        exclusive.add_argument("--metadata-dump", action="store_true", default=False, dest='dump',
                               help='**For internal testing only** Dump json metadata for all plugins.')
    def post_process_args(self, options):
        options = super(DocCLI, self).post_process_args(options)
        display.verbosity = options.verbosity
        return options
    def run(self):