* Provide a better visualization of the the different test suites
 * Migrate setup instructions from https://github.com/civicrm/civicrm-core/blob/master/tests/README.md

1. Add new entries for Protractor, Codeception, and QUnit

2.  This menu includes (a) some pages about the overall testing process and
(b) some pages about specific tools.  Consistently put the general before
the specific.

There are multiple tools for testing in JS. We'll want separate pages for each.

The second statement doesn't make much sense without the first statement.
Put them together.

Running civilint is important for any/all code.  Seems a bit arbitrary
emphasizing this point specifically for tests.

Move tokens docs into User Guide

related:
https://github.com/civicrm/civicrm-user-guide/pull/232

Resolve #316

Document API lookups by username

mkdocs.yml - Simplify menu headings

Per discussion of https://github.com/civicrm/civicrm-dev-docs/pull/434

When scanning the navbar, there are several words which (IMHO) aren't adding
much value.  This simplifies and should make it easier to navigate.

change path in Entity creation w/flow

framework/filesystem.md - Cleanup prose. Add table of `civicrm.files` subdirs.

documentation/style-guide.md - Mention bash portability tip

Add "Review Standards"

If a reader has customized their interactive shell, their system could have
small discrepancies in shell notation.  It shouldn't matter 95% of the time,
and it's not critical to support those folks perfectly.  But it is nice.  So
let's just share the link to heighten awareness.

(Example: I usually do `export VAR=value`...  but in future docs, I'll try
to use `VAR=value; export VAR`.)

This is following-up on some comments from @ginkgomzd who found the
`bash-hackers.org` site and shared it on https://github.com/civicrm/civicrm-buildkit/pull/365

 * Simplify titles under "Common standards". (Use a noun-phrase instead of an imperative statement.)
 * Combine `r-ext`, `r-core` into r-technical. Add more details. Reference `#gotchas`.
 * Rename `r-read` to `r-code`
 * Rename `rg-schema` to `rg-upgrade`. Add more details.

Add warning about TRUNCATE TABLE to PHPUnit Tests doc.

standards/php.md - Add a TLDR example

To see actual examples of the coding style, you need to skim multiple blurbs
and click multiple links, and the eventual page shows very isolated
examples.

This revision adds a brief example so that a new contributor can get a
general sense of the layout immediately.

(Note: It's not possible for a brief example to show every edge-case, and we
shouldn't try -- that's why the commit also emphasizes the link into the
relevant examples from d.o docs.)