Have a way to list versions in interactive mode of project init

[tailhook]

The complex part here is:

1. By default 2.14 means >= 2.14, < 3. Same goes for testing channel.
2. Wee don't allow to pin nightly.
3. Showing version 2.13 in the list doesn't make sense (2.14 will be installed anyways, unless pinning is used), but user can still type 2.13, if they know that this is a minimum version having the right bugfix and we will accept that version number.