Re-add jQuery output to the assets.yaml

Otherwise the Chrome extension doesn't get the jQuery file copied
into it's public folder. Also had to rename jQuery to include the
version string as Webassets will skip an asset entirely if the output
filename matches the content filename. This causes the embed.js loader
 to skip the loading of jQuery completely.
Merge pull request #1706 from hypothesis/add-jquery-asset

Re-add jQuery output to the assets.yaml