Package cleanup: reduce published files and dependencies (#126, #127)

[thibaudcolas]

Addresses #126 and #127 in a single PR.

I don’t think there is a way to test the dependencies removal apart from npm installing the published package. For the removal of unneeded files, here is the command I would recommend using, to inspect what would be part of the package’s tarball on npm publish:

npm pack --loglevel notice 2>&1 >/dev/null | sed -e 's/^npm notice //' && rm *.tgz

And here is the diff of that command’s output before and after the switch from .npmignore to the package.json files:

📦  sass-resources-loader@2.1.0
=== Tarball Contents ===
-0     .idea/test
-0     .vscode/test
1.1kB LICENSE
1.5kB lib/utils/flattenArray.js
2.8kB lib/utils/getOptions.js
292B  lib/utils/isArrayOfStrings.js
-115B  jest.config.js
2.9kB lib/loader.js
2.3kB lib/utils/logger.js
1.0kB lib/utils/parseResources.js
1.4kB lib/utils/processResources.js
1.8kB lib/utils/rewriteImports.js
1.8kB lib/utils/rewritePaths.js
-1.6kB package.json
+1.7kB package.json
2.5kB CHANGELOG.md
-1.4kB CODE_OF_CONDUCT.md
-2.6kB CONTRIBUTING.md
9.8kB README.md
-20B   .github/FUNDING.ym
=== Tarball Details ===
[...]
-package size:  10.8 kB
+package size:  9.1 kB
-unpacked size: 35.0 kB
+unpacked size: 30.9 kB
[...]
-total files:   19
+total files:   13

Note how even if the pattern is only lib, npm will always include the project’s package.sjon, README, license, and CHANGELOG.

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This change is 

[justin808]

@thibaudcolas Thanks!

[justin808]

@thibaudcolas please try out v2.1.1.