Erase the postinstall script before publishing a new version

[novusnota]

This is needed to circumvent the same npm issues Tact compiler had prior to releasing the version 1.6.2.

Here's what you need:

1. Make sure everything's committed
2. Remove the postinstall lifecycle script (temporarily): jq 'del(.scripts.postinstall)' package.json -M > temp.json && mv temp.json package.json
3. Do the regular pre-release steps, then do npm publish (or somesuch)
4. Finally, revert changes to the package.json: git checkout -- package.json

[novusnota]

Or just remove the script from package.json altogether, similar to how tact-lang/tact did it.

[anton-trunov]

It's already been done on npmjs, we just need to update the codebase to reflect it, see #59