Upgrade Docker image to Alpine 3.11

[languitar]

This make tesseract 4.1 avaialbe, which fixes some things like infinite
processing loops on some documents:
tesseract-ocr/tesseract#2288 (comment)

Some dependencies had to be bumped for being compatible with the new Alpine
libraries.

[languitar]

Travis failure seem to be unrelated to my changes. They originate from the sphinx documentation :/

[Tooa]

Travis failure seem to be unrelated to my changes. They originate from the sphinx documentation :/

@languitar @bauerj Merge PR #601 first to fix this issue

How is this related to upgrading the operating system?

Had to add the protocol to CORS_ORIGIN_WHITELIST too. It seems like a required fix. See #600 /Open Questions 1.

[Tooa]

Thanks for taking the time to upgrade Alpine in order to fix issues with tesseract. I have no complaints merging your changes. Generally, it would be nice to separate changes that are not part of the main PR feature in its own commit.

• Conducted tests
  • docker-compose build works
  • All unit-tests still succeed
  • PDF documents are processed
  • OCR output looks fine

---

Maybe I found something:

• After the first docker-compose up, I added PAPERLESS_OCR_LANGUAGES=deu and PAPERLESS_OCR_LANGUAGE=deu to both containers. The log of the consumer shows me:

sudo: setrlimit(RLIMIT_CORE): Operation not permitted
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, documents, reminders, sessions
Running migrations:
  No migrations to apply.
fetch http://dl-cdn.alpinelinux.org/alpine/v3.11/main/x86_64/APKINDEX.tar.gz
fetch http://dl-cdn.alpinelinux.org/alpine/v3.11/community/x86_64/APKINDEX.tar.gz
(1/1) Installing tesseract-ocr-data-deu (4.1.0-r0)
OK: 308 MiB in 128 packages
sudo: setrlimit(RLIMIT_CORE): Operation not permitted

[pitkley]

@languitar thanks for the PR, dependency updates are always nice! #601 is just missing another review from @the-paperless-project/reviewers, then you can rebase on master to fix the Travis issue.

Regarding the setrlimit(RLIMIT_CORE) error/warning @Tooa mentioned: a simple fix is to echo 'Set disable_coredump false' >> /etc/sudo.conf, see https://ask.fedoraproject.org/t/sudo-setrlimit-rlimit-core-operation-not-permitted/4223 and https://gitlab.alpinelinux.org/alpine/aports/issues/11122. Maybe the suggested doas-change in the latter link is a more correct fix, but I think that would be too big for what this PR should be doing.

Feel free to ping me directly for a review once the Travis build is fixed. 👍

[languitar]

I have rebased the PR, added the setrlimit fix, and split the PR into two distinct commits with further clarifications.

[pitkley]

I checked the major dependency updates as best I could and didn‘t find any incompatibilities that should affect us (besides the already fixed CORS whitelist).