Change "main" script in package.json

[toptalo]

Need to change "main" script in package.json for correct requre() in node

now: "main": "./src/index.js",
need: "main": "./dist/node-parserlib.js",

Also wil be better to exclude src dir from package for size decrease

[toptalo]

I can do PR if this idea fits

[toptalo]

Here it is #237