Remove development files

git-svn-id: https://plugins.svn.wordpress.org/aviation-weather-from-noaa/trunk@1054233 b8457f37-d9ea-0310-8a92-e5e31aec5664
Cast as bool instead of using boolval() to allow for < PHP 5.5

git-svn-id: https://plugins.svn.wordpress.org/aviation-weather-from-noaa/trunk@1054235 b8457f37-d9ea-0310-8a92-e5e31aec5664