Bug in directory exclusion logic in ClasspathResolver.

[seadbrane]

There is an issue in 0.9.14 (at least with some classloaders) in ClasspathResolver line 43, where getResource returns a non null URL for non-existent paths in the JAR which results in assuming it is a directory, when it is actually a valid classpath template resource.

 43                } else if (ccl.getResource(normalizeResourceName + "/") != null) {
 44                     // This is a directory
 45                     return null;
 46                 }'

Proposed fix:

-                } else if (ccl.getResource(normalizeResourceName + "/") != null) {
-                    // This is a directory
-                    return null;
+                }
+                // Use JarURLConnection to accurately check if this is a directory in the jar
+                try {
+                    JarURLConnection jarConn = (JarURLConnection) resource.openConnection();
+                    JarEntry entry = jarConn.getJarEntry();
+                    if (entry != null && entry.isDirectory()) {
+                        return null;
+                    }
+                } catch (IOException e) {
+                    // If we can't check, assume it's a file and proceed