Extract Emojis code into npm package

Because the scripts are just copied over from the main GitLab project (!62 (merged)), they are going to fall out of sync from each other. It looks like the work is done to extract the pieces in the MR so this could become a new npm package that we could share here and on GitLab (@gitlab/gl-emoji).

Based on the conversation #28 (comment 321362536) it would be very convenient to Extract emojis generation into separate npm package to pull in as a dependency into Status Page project, GitLab as well as any upcoming projects that would need emojis