CollectionInputFilter throws warning if invalid collection provided(not traversable)

throws php Warning: `Invalid argument supplied for foreach()`
removed trailing spaces
removed all trailing spaces
Merge pull request #6494 from svycka/patch-2

CollectionInputFilter throws warning if invalid collection provided

Conflicts:
	tests/ZendTest/InputFilter/CollectionInputFilterTest.php
[#6494] Fix for provided unit test

- Scalar data cannot be validated, and should be considered false.
Merge branch 'hotfix/6494'

Fixes #6494