Zend\Form - trying to get() a non-existent element should raise an exception
Zend\Form - Exception when try to get() element that doesn't exist should use sprintf, message should not use punctuation & should not import the exception class
Merge branch 'hotfix/4546'

Close #4546
Fixes #4545
Merge pull request #4572 from joshribakoff/master

Zend\Form Should throw exception if try to get() an element that does not exist
[#4572] Break test case/provider into 2

- PHPUnit under PHP 5.3.3 was throwing segfaults when run with no
  arguments, and yet passing fine when given --tap and other arguments.
  Based on experimentation, it appeared to be solely based on the number
  of items in the data provider. Split the data provider and test case
  into two, and all problems were solved.
Merge branch 'hotfix/4572' into develop

Forward port #4572