Handle infinite, endless and beginless ranges

[xunker]

We can do endless ranges in Ruby < 2.6 with (0..Float::INFINITY), and in Ruby >= 2.6 with (0..) or (0..nil).

Also, in Ruby 2.7 we now have beginless ranges: [..100]

These may already work, because they can be worked with as an array, but we need to add tests for that.

[a0960909060]

helpers/build-app-list.js