new ejs data (weakmap/weakset/misc others)
Merge pull request #368 from toshok/latest-ejs-update

new ejs data (weakmap/weakset/misc others)
Fix Error stack test. Thanks @simevidas
Separated Chrome results into flagged and unflagged values.

Now, Chrome features only available as "Experimental Javascript Features" are marked with a special cell, and do not contribute to its ES6 support percentage.
Fixed some resuls and minor build.js issues.