Always use preserveComment: 'some'
grunt
Nuke equal height columns example; got a few bugs that make it not ready for prime time in v3.2
Update JSZip to v2.3.0.
Use full deprecation version
Merge pull request #13865 from BBosman/deprecated

Use full deprecation version
Merge pull request #13829 from BBosman/preserve

Always use preserveComment: 'some'
Run `grunt`.