Clean up redundant descriptions and broken help on import forms

[larssandergreen]

Overview

Just a bit of UI clean up to make the first step of the import forms less busy and more functional. Also removed some very lengthy help texts that were not accessible from anywhere, so were just translation work for no benefit (this detail is covered, better, in the docs).

Before

Redundant descriptions, help doesn't work on some non-contact import form links, incorrect text.

For example:

After

Cleaner, help text works, removed incorrect text.

[civibot]

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[larssandergreen]

jenkins, test this please

[mlutfy]

Spotting the differences was not super obvious to my sleep-deprived mind, but once you see them, I think they make sense.

I tested the patch and works for me.

Thank you @larssandergreen !

[larssandergreen]

Thanks @mlutfy