Updated admin zen_not_null to bring it in line with the non admin function.
The primary concern with the admin one was zen_not_null(true) === false
The website one correctly does zen_not_null(true) === true
An explicit check for boolean could also be added but I guess it doesn't need it.
Merge pull request #42 from robryanx/v160

Updated admin zen_not_null to bring it in line with the non admin function
CHANGE-18 - Installer - update version-detection rules to test for buggy CGI versions of PHP
CHANGE-18 - Installer - update version-detection rules to test for buggy CGI versions of PHP
CHANGE-696 - refactoring previous commit: Display of Product Categories is unclear and needs better layout
Administrative - updating build status in readme
CI testing updates
CI testing updates
CI testing updates
CI testing updates
CI testing updates
Administrative - updating build status in readme
CI testing
CI testing
CI testing
CI testing
Suspend sauce tests temporarily
Merge pull request #57 from zencart/v160

zc 160