Support jsdoc and typedoc doctools

[humitos]

We need to pin these dependencies to make the image reproducible over time:

https://github.com/rtfd/readthedocs-docker-images/blob/89bb0b60820ab0960d5cc875667ba2570c5ffb99/Dockerfile#L128-L130

[humitos]

Versions on images from production today:

(docs) docs@build-default-i-0a1801f3c8ed1d18c:~$ docker run readthedocs/build:5.0 jsdoc --version
JSDoc 3.6.6 (Sun, 20 Sep 2020 02:25:14 GMT)
(docs) docs@build-default-i-0a1801f3c8ed1d18c:~$ docker run readthedocs/build:6.0 jsdoc --version
JSDoc 3.6.6 (Sun, 20 Sep 2020 02:25:14 GMT)
(docs) docs@build-default-i-0a1801f3c8ed1d18c:~$ docker run readthedocs/build:7.0 jsdoc --version
JSDoc 3.6.6 (Sun, 20 Sep 2020 02:25:14 GMT)

typedoc --version is failing, but I'd guess by the date the docker images were built that:

• 5.0 (built 9 months ago) has typedoc 0.19.2
• 6.0 (built 9 months ago) has typedoc 0.19.2
• 7.0 (built 5 months ago) has typedoc 0.20.20

I can support this guess by parsing the package.json:

(docs) docs@build-default-i-0a1801f3c8ed1d18c:~$ docker run --rm -it readthedocs/build:7.0 cat /usr/local/lib/node_modules/typedoc/package.json | grep version
  "version": "0.20.20"
(docs) docs@build-default-i-0a1801f3c8ed1d18c:~$ docker run --rm -it readthedocs/build:6.0 cat /usr/local/lib/node_modules/typedoc/package.json | grep version
    "postbuild": "node scripts/replace_application_version.js",
  "version": "0.19.2"
(docs) docs@build-default-i-0a1801f3c8ed1d18c:~$ docker run --rm -it readthedocs/build:5.0 cat /usr/local/lib/node_modules/typedoc/package.json | grep version
    "postbuild": "node scripts/replace_application_version.js",
  "version": "0.19.2"

Reference: https://www.npmjs.com/package/typedoc

[humitos]

Building 7.x using #174 generates this warning message

npm WARN [email protected] requires a peer of [email protected] || 4.0.x || 4.1.x but none was installed.

I'm not sure if it's important or not and I think it was already present in this image. Maybe typedoc --version breaks because of that? 🤔

[humitos]

I'm thinking about how to handle this case in the new images (#166). I prefer if we don't include these at this moment because we will need to handle versioning again on the base image. I'm not aware how many users are currently using these packages and if there is a good way to install them (without hacking the conf.py).

On the other hand, these are documentation tools (like Sphinx or MkDocs). Because of that, if we want to support them, we should allow them to be installed as any other doctool. I'd like to add support for them on the "Future builders" when we allow custom commands.

[humitos]

It seems this is not required anymore. New Docker images does not include jsdoc nor typedoc and they could be installed using build.apt_packages.