Missing examples for HMR

[datenreisender]

In https://github.com/TypeStrong/ts-loader#hot-module-replacement two example project setups for HMR are referenced, which were deleted in #899. Please describe more thoroughly in README.md what was once in the examples. I am at the moment struggling with setting up HMR and as a guidance tried to look at the examples before they were removed but also failed to make them work. :-/

[johnnyreilly]

I recommend looking at an older version of the repo if you want to see the examples. It was removed as the HMR example had some problems. As I understand it hmr has never really worked reliably enough for me to be comfortable having an example in the repo. If that changes I'd be happy to readdress. We should really remove reference to old examples from the repo

[datenreisender]

If for you, as you wrote, "hmr has never really worked reliably enough" then I suggest adding an according warning to the section of the README, besides removing the reference to the old examples. My suggestion for that section:

### Hot Module replacement

We do not support HMR as we did not yet work out a reliable way how to set it up. 

If you want to give `webpack-dev-server` HMR a try, follow the official [webpack HMR guide](https://webpack.js.org/guides/hot-module-replacement/), then tweak a few config options for `ts-loader`:

1. Set `transpileOnly` to `true` (see [transpileOnly](#transpileonly-boolean-defaultfalse) for config details and recommendations above).
2. Inside your HMR acceptance callback function, maybe re-require the module that was replaced.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

Closing as stale. Please reopen if you'd like to work on this further.

[brainkim]

Might want to update this part of the README https://github.com/TypeStrong/ts-loader/#hot-module-replacement rather than pointing to dead example links.

[johnnyreilly]

Would you like to submit a PR?