Previously, the "Copy markdown" button in the playground generated
markdown containing this when having selected "babel-flow" as parser:
```babel-flow
This commit changes it to:
```jsx
So that the code blocks get syntax highlighting on GitHub.
This pull requests adds a new parser option `lwc`. This is the same as the HTML parser, but it adds support for unquoted HTML attributes per the needs of LWC. See: #5627
- switch to [`htmlparser2`](https://github.com/fb55/htmlparser2)
- no need to fork
- won't generate pseudo nodes ([`parse5` will](https://github.com/prettier/prettier/issues/5098#issuecomment-423055181))
- should be [faster](https://github.com/fb55/htmlparser2#performance)
- support custom self-closing tags
- support HTML entities
- remove extra trailing newline for `<template>`
- distinguish empty/empty-string attributes (`<tag x>`/`<tag x="">`)
- rename `--parser parse5` with `--parser html`
- enable `html` since 1.15, which means it's enabled by default if you install the dev version from GitHub after this PR merged.
Simon Lydell