Add main field to package json

[zemeolotu]

This PR add main field in package json for @finos/perspective , @finos/perspective-viewer, @finos/perspective-viewer-datagrid and @finos/perspective-viewer-d3fc.

[finos-cla-bot]

Thank you for your contribution and Welcome to our Open Source Community!

To make sure your pull request is successful, we need all our contributors to be identifiable, but we couldn't parse the GitHub details of the following people : Zeme

Luckily, resolving the issue is straightforward and you can resolve it by following the instructions below.

1. Check your git client is configured with a user email git config --list | grep email
2. If the user email is missing, run the following command, substituting with your git commit email address git config --global user.email [email protected]
3. Make sure your git commit email is configured on GitHub by Setting your Commit Email Address
4. Then, amend the authors in your commit history by using git commit --amend to change your last commit.

Alternatively, use the slightly more complex git reset --soft and git rebase to checkout your changes, rewrite the commit history locally and (force) push changes to the downstream branch.

If you have any issues with the steps above, please email [email protected] so we can help you resolve before reviewing and accepting your pull request.

Thanks once again for the contribution and understanding.

cc @finos-admin

[texodus]

Thanks for the PR! Looks good!

As discussed, I'm not 100% clear of the impact of this change for all possible permutations of tools, so we'll need to keep a close eye on errors stemming form the 1.3.4 release.