Remove default geopoint hint

[tiritea]

Steps to Reproduce

…add geopoint question to form but dont add any hint
…preview form in Enketo
…

Expected behavior

no hint

Actual behavior

see default hint "GPS coordinates can only be collected when outside."

Additional details

Always displaying a default hint is not really appropriate, and indeed this particular hint is not even correct (it is quite possible to get a GPS fix inside a house or building)

I cant find anything in the actual code to remove this using a PR. I suspect the hint is getting copied out of one of the template spreadsheets (base.xls or all.xls) and used to initialize geopoint hint in any new form definition otherwise lacking a corresponding user-defined hint.

In general, I dont believe the pyxfom tool should be adding any new semantic content into a form (even if well intentioned...). If the form writer wants a suitable hint in their form then it is their responsibility to explicitly define one. And if they dont want a hint then it should be possible not to have one [sic].

[lincmba]

This is no longer an issue in Pyxform.
It was addressed in this PR #67