sync svn r24702 - support application/x-zip in Validator\File\IsCompressed

This is a sync of svn r24702.
for support application/x-zip 

@see (commit-log)
https://bitbucket.org/sasezaki/mirror-zf1-standard-trunk-libraray-validate-dir/commits/deab989ef3728529ff4f0f35aba7ca6498643523
https://bitbucket.org/sasezaki/mirror-zf1-standard-trunk-tests-validate-dir/commits/c11495d2a6d3f191694820f9a9b6b7938a062fa8

original commit is using mime_content_type() function (yeah, it is deprecated) , so should be attention before merge this.