WIP - add extractor, generate snippet_data

node_modules/gatsby-transformer-sharp/README.md

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+# gatsby-transformer-sharp
+
+Creates `ImageSharp` nodes from image types that are supported by the
+[Sharp](https://github.com/lovell/sharp) image processing library and provides
+fields in their GraphQL types for processing your images in a variety of ways
+including resizing, cropping, and creating responsive images.
+
+[Live demo](https://image-processing.gatsbyjs.org/)
+([source](https://github.com/gatsbyjs/gatsby/tree/master/examples/image-processing))
+
+## Install
+
+`npm install --save gatsby-transformer-sharp gatsby-plugin-sharp`
+
+## How to use
+
+```javascript
+// In your gatsby-config.js
+module.exports = {
+  plugins: [`gatsby-plugin-sharp`, `gatsby-transformer-sharp`],
+}
+```
+
+Please note that you must have a source plugin (which brings in images) installed in your project. Otherwise, no `ImageSharp` nodes can be created for your files. Examples would be [`gatsby-source-filesystem`](/packages/gatsby-source-filesystem) or source plugins for (headless) CMSs like [`gatsby-source-wordpress`](/packages/gatsby-source-wordpress).
+
+**Note**: An exception to this is when using [`gatsby-source-contentful`](/packages/gatsby-source-contentful/), as the source plugin and the assets are not [downloaded to the local filesystem](https://www.gatsbyjs.org/packages/gatsby-source-contentful/#download-assets-for-static-distribution). By default, the `gatsby-source-contentful` plugin creates a `ContentfulAsset` node for every image with links to Contentful’s CDN, therefore it is not necessary to use `gatsby-transformer-sharp` together with `gatsby-source-contentful`.
+
+## Parsing algorithm
+
+It recognizes files with the following extensions as images.
+
+- jpeg
+- jpg
+- png
+- webp
+- tif
+- tiff
+
+Each image file is parsed into a node of type `ImageSharp`.
+
+## Troubleshooting
+
+### Incompatible library version: sharp.node requires version X or later, but Z provides version Y
+
+This means that there are multiple incompatible versions of the `sharp` package installed in `node_modules`. The complete error typically looks like this:
+
+```
+Something went wrong installing the "sharp" module
+
+dlopen(/Users/misiek/dev/gatsby-starter-blog/node_modules/sharp/build/Release/sharp.node, 1): Library not loaded: @rpath/libglib-2.0.dylib
+  Referenced from: /Users/misiek/dev/gatsby-starter-blog/node_modules/sharp/build/Release/sharp.node
+  Reason: Incompatible library version: sharp.node requires version 6001.0.0 or later, but libglib-2.0.dylib provides version 5801.0.0
+```
+
+To fix this, you'll need to update all Gatsby plugins in the current project that depend on the `sharp` package. Here's a list of official plugins that you might need to update in case your projects uses them:
+
+- `gatsby-plugin-sharp`
+- `gatsby-plugin-manifest`
+- `gatsby-remark-images-contentful`
+- `gatsby-source-contentful`
+- `gatsby-transformer-sharp`
+- `gatsby-transformer-sqip`
+
+To update these packages, run:
+
+```sh
+npm install gatsby-plugin-sharp gatsby-plugin-manifest gatsby-remark-images-contentful gatsby-source-contentful gatsby-transformer-sharp gatsby-transformer-sqip
+```
+
+If updating these doesn't fix the issue, your project probably uses other plugins from the community that depend on a different version of `sharp`. Try running `npm list sharp` or `yarn why sharp` to see all packages in the current project that use `sharp` and try updating them as well.