Add container examples to documentation, clean up README

[jaredpetersen]

This is a multipart documentation update.

I added code samples for how to use Testcontainers-Go with CockroachDB, Redis, and NGINX per the discussion in #112 and #351. I've run all of the example code to make sure that everything completes as expected.

I know there are more examples from past closed PRs for things like Minio, MongoDB, and Postgres that the old canned modules documentation referenced. However, since canned modules are now a dead concept, sharing that code won't be very helpful and it needs some tweaking in order to fit into this new example-based documentation model. I'd like to contribute Postgres, MySQL, and Kafka + Schema Registry examples too but I'll need more time for those. This is a good starting point though and we can begin helping people now rather than later.

I also updated the README a bit so that it uses language from more of a project perspective rather than an individual author perspective per #351. I also found that the existing NGINX example no longer compiles because it referenced a no longer existing Terminate(ctx context.Context, t *testing.T) function.

The project description on GitHub has a grammatical issue that should be fixed. The word "provides" should be used instead of "providing":

...Golang library that providing a friendly API...

However, I would instead suggest replacing the project description entirely with the following:

Testcontainers-Go is a Go package that makes it simple to create and clean up containers for automated tests

It just needs to be small, quick hook rather than a two sentence summary 🙂

[jaredpetersen]

CC @mdelapenya since we last talked about docs in one of the linked issues. No rush here necessarily though.

[codecov]

Codecov Report

Merging #353 (429451f) into master (a8ca295) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #353   +/-   ##
=======================================
  Coverage   61.91%   61.91%           
=======================================
  Files          15       15           
  Lines        1011     1011           
=======================================
  Hits          626      626           
  Misses        288      288           
  Partials       97       97           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update a5a9803...429451f. Read the comment docs.

[mdelapenya]

Hey @jaredpetersen this LGTM, although there are conflicts in the modules section (a PR was merged with kafka canned container). Could you please resolve them? I will approve these changes right after, as I see them as a great improvement for the project. Great job with the clean-up!!

[jaredpetersen]

I'll get on that conflict ASAP. Thanks for reviewing 👍

[jaredpetersen]

Fixed those conflicts, ready for review again.

[mdelapenya]

Sorry for the delay 🙏 AND this LGTM 👍