Consistent project samples and gifs

[sgammon]

Issue description

The Gifs use command aliases like elide.dev and elide.opt, which are local development aliases for the dev/opt versions of Elide. It is probably confusing to users to download Elide and find it at elide instead on their PATH.

Separately, we should list project samples in a uniform way in the README and docs, and link to them on GitHub.