Supplying GPG key password into Pass command

[Daniel Long Sockwell]

Hi Louis,

I tend to agree with Anne that you *generally* shouldn't need pipe in
the password for the GPG key.  However, if you still want to, you can do
so by setting the `PASSWORD_STORE_GPG_OPTS` environmental variable to
`--yes --batch --passphrase=YOUR_PASSWORD` (with `YOUR_PASSWORD`
replaced by your actual password, of course).

Best regards,
Daniel