Fixed typo

It's `[NSArray class]` not `[NSArray array]`. Bites me every single time

git-svn-id: http://ios.svn.wordpress.org/trunk@4059 7d847f7c-ffe1-4a24-85be-b788d016d96a
Don't construct the push notification call arguments with nil values

In some cases where password was nil, there was only one parameter, as
`arrayWithObjects:` stops processing on nil

git-svn-id: http://ios.svn.wordpress.org/trunk@4060 7d847f7c-ffe1-4a24-85be-b788d016d96a
Add more checks for nil passwords

git-svn-id: http://ios.svn.wordpress.org/trunk@4061 7d847f7c-ffe1-4a24-85be-b788d016d96a
Bump version to 3.4.1

git-svn-id: http://ios.svn.wordpress.org/trunk@4062 7d847f7c-ffe1-4a24-85be-b788d016d96a