force encoding on all queries

this applies 4e29b8a7 to everything

I've since gotten an account with +foobar@gmail.com suffix and confirmed
it too needs encoding to properly log in as well.
So does a product with the name 'foo+bar'. I've deduced that bugzilla's
query handling simply always assumes full encoding WRT the plus character
and so we'll force full encoding through the HTTPConnection to always
use full encoding (i.e. including the plus character)

CCBUG: 413920