cmd/upspin: accept the user name in -put
cmd/upspin: accept the user name in -put

Many users have tried this and failed:

upspin user -put me@example.com <user_record.txt

This change accepts that format if the given name matches
the one in the input file.

Change-Id: Ifadf12747f678f0fbb36c7efccc0fcd2e8cb0d11
Reviewed-on: https://upspin-review.googlesource.com/8082
Reviewed-by: Andrew Gerrand <395a7d33bec8475c9b83b7d440f141bcbd994aa5@golang.org>
Reviewed-by: Rob Pike <4dc7c9ec434ed06502767136789763ec11d2c4b7@golang.org>

upspin/upspin,upspin/upspin