Replace relevance with "Show question if"

[lognaturel]

Users don't know what relevance means. It would also really help to show an example (something simple like /data/age > 10 -- only show this question if the question named age has a value above 10).

See https://forum.opendatakit.org/t/guide-me-on-setting-up-skips-on-build/13739 for a user who doesn't know where to start.

[issa-tseng]

the reasoning behind the naming was the combination of:

1. it's an advanced feature, and
2. adhering to the existing norms (both xform and xlsform).

so the theory was that the people who would have any idea what to do with it would look for "relevance"/"relevant" and understand what to do with it.

that said, very happy to see it changed. just wanted to give context.

[lognaturel]

That makes sense! I do think there's a nice opportunity to make an important feature easier to discover and use. It also leads to a lot of questions on the forum.

Of course if you're not sure about the wording, I'm not to wedded to my suggestions, I just wanted to put some suggestions out!

[issa-tseng]

resolved in #216.