feat: changelog endpoints (#543)

* refactor: make `pushDoc` more generic

... so we can reuse it for Changelog! 🚀

No functional changes were made, docs tests should still pass.

* chore: camelcase filePath, grammar tweaks

* test: split out fixtures

* chore: add changelog command category, rearrange

* feat: initial pass at changelog commands

* test: add test suite

let's hope this is right lol

* docs: update README.md

* test: use fixtures in changelog subdir

Author: kanadgupta

README.md

@@ -171,6 +171,26 @@ rdme docs:edit <slug> --version={project-version}
 rdme docs:single path-to-markdown-file --version={project-version}
 ```
 
+### Changelogs
+
+#### Syncing a Folder of Markdown to ReadMe
+
+The Markdown files will require YAML front matter with certain ReadMe documentation attributes. Check out [our docs](https://docs.readme.com/docs/rdme#markdown-file-setup) for more info on setting up your front matter.
+
+Passing in a path to a directory will also sync any Markdown files that are located in subdirectories.
+
+```sh
+rdme changelogs path-to-markdown-files
+```
+
+This command also has a dry run mode, which can be useful for initial setup and debugging. You can read more about dry run mode [in our docs](https://docs.readme.com/docs/rdme#dry-run-mode).
+
+#### Syncing a Single Markdown File to ReadMe
+
+```sh
+rdme changelogs:single path-to-markdown-file
+```
+
 ### Versions
 
 #### Get All Versions Associated With Your Project

__tests__/__fixtures__/changelogs/existing-docs/not-a-markdown-file

@@ -0,0 +1,4 @@
+---
+title: This is the changelog title
+---
+Body

__tests__/__fixtures__/changelogs/existing-docs/simple-doc.md

@@ -0,0 +1,4 @@
+---
+title: This is another changelog title
+---
+Another body

__tests__/__fixtures__/changelogs/existing-docs/subdir/another-doc.md

@@ -0,0 +1 @@
+Body

__tests__/__fixtures__/changelogs/failure-docs/fail-doc.md

@@ -0,0 +1,6 @@
+---
+type: added
+title: This is the changelog title
+---
+
+Body

__tests__/__fixtures__/changelogs/failure-docs/new-doc.md

@@ -0,0 +1,6 @@
+---
+type: added
+title: This is the changelog title
+---
+
+Body

__tests__/__fixtures__/changelogs/new-docs/new-doc.md

@@ -0,0 +1,7 @@
+---
+type: added
+title: This is the changelog title
+slug: marc-actually-wrote-a-test
+---
+
+Body