allow a null page in construct array, to compensate for ZF issue #3823
add unit test
Merge branch 'hotfix/nav-null-page' of git://github.com/nclundsten/zf2 into hotfix/3840
[#3840] Added group annotations to new test

- per comment from @Freeaqingme
Merge branch 'hotfix/3840'

Close #3840
Fixes #3823