Update changelog for v0.3.4

Bump version to 0.3.4 for publishing

Update browser bundle

Ignore zoom events without event object (fixes #51)

Updated dependencies

Fix documentation

Add binary graph operators

Add Set union and symmetricDifference

Reduce npm scripts redundancies

Fix typo in readme

Update changelog for v0.3.3

Bump version to 0.3.3 for publishing

Update browser bundle

Fix plugin to work with latest Babel

Enable and simplify custom browser builds