imports: improve VendorlessPath docs
imports: improve VendorlessPath docs

Eliminate Latin, lest someone complain
"it's Greek to me".

This work supported by Sourcegraph,
though perhaps not the commit message.

Change-Id: Ia44eaf5bc5adb6624b590c9cfdfe8083d1414a2c
Reviewed-on: https://go-review.googlesource.com/108937
Run-TryBot: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools