Check if there are conflicts on master when running the build

- This is taken from
  https://github.com/alphagov/specialist-publisher/commit/9a097249c142c6e7146706dfd5fc0282c92f4886,
  as a thing discussed in tech lead standup that could be useful and
  passed to me to do via Jamie.
Merge pull request #74 from alphagov/jenkins_test_merge_result_of_branches

Check if there are conflicts on master when running the build
Fix rendering of the README in the app

* Add a missing line break before a list to make it work
* Fix rendering of code blocks in the response code list by switching to
  indented syntax
* Inline the URL standards link into a sentence
* Capitalise some header names and the word "Markdown"
Mark up header names and HTTP statuses as code

Just to make it consistently clear that these are Computer Things.
Use indented code blocks everywhere

Since commit 912306992084e1a1cf350ce19075a8c962a579fe, we're using
intended syntax for multi-line code blocks (Kramdown doesn't understand
GitHub's fenced code block syntax, so they don't render as <pre> blocks
in the app), so we might as well use them consistently.
Merge pull request #75 from alphagov/readme-tweaks

A miscellany of README fixes
Log request body with Logstasher

This is a temporary measure to help debug markdown rendering issues.
It should log the request body as a separate field in the JSON logs
which go into Kibana.
Merge pull request #76 from alphagov/log_request_body

Log request body with Logstasher
Handle request.body being a StringIO when logging it

- need to read it, not log the object
- need to rewind it before and after reading it so that it can be read again
Merge pull request #77 from alphagov/log_request_body_not_object

Handle request.body being a StringIO when logging it
Include the format in search documents

We should include the format of the document so that it can be used in the
search index for various things, such as weighting the format up and down.

More specifically/imminently, we want to display the format in search results
to give users context on what the search result is when HMRC Manuals and
sections appear in search results.
Merge pull request #78 from alphagov/include_format_in_search_documents

Include the format in search documents
Add feature flag for logging request body, disabled by default

We only want to log the request body in Preview, because it could use
up quite a lot of disk space if manuals are published in large volumes.
Merge pull request #79 from alphagov/feature_flag_log_request_body

Add feature flag for logging request body, disabled by default
Specify that we use the Kramdown Markdown dialect
Merge pull request #80 from alphagov/specify_markdown_dialect

Specify that we use the Kramdown Markdown dialect
Change the hmrc-manuals GOV.UK prefix to hmrc-internal-manuals

- These manuals aren't normal manuals, they're internal manuals
  published solely because of FoI requests. End users should therefore
  be made aware that they're different (and in a different style, etc.)
  hence this change.
- Things have to change here AND in manuals-frontend, 'cause we push to
  the publishing API and that has to realise that the URL has changed.
Return the status code from the Publishing API to the client

In production, Rummager queues search index updates so returns 202
to POST requests to insert or overwrite a document:

https://github.com/alphagov/rummager/blob/cc0e9c95db9098b0dbc3dd12124d1eef5a153ae7/app.rb#L460-L466

We have been returning the status code from Rummager to the client,
which is inconsistent with the documentation in the README. It also
seems inaccurate: the content has been saved to the content-store
already and so can be displayed on GOV.UK, so 200/201 is more appropriate.

This commit switches to returning the Publishing API response status
code to the client. It also bumps the version of gds-api-adapters to
pick up the addition of a test helper which stubs a POST request to
Rummager as if queueing is enabled.
Merge pull request #83 from alphagov/return_publishing_api_status

Return the status code from the Publishing API to the client
Merge pull request #82 from alphagov/change_hmrc_manuals_govuk_prefix

Change the hmrc-manuals GOV.UK prefix to hmrc-internal-manuals