FELIX-6536: use FileSeparator to work correctely on Windows (#155)

diff --git a/framework/src/main/java/org/apache/felix/framework/cache/DirectoryContent.java b/framework/src/main/java/org/apache/felix/framework/cache/DirectoryContent.java
index 3e4a2ad..624c541 100644
--- a/framework/src/main/java/org/apache/felix/framework/cache/DirectoryContent.java
+++ b/framework/src/main/java/org/apache/felix/framework/cache/DirectoryContent.java
@@ -67,7 +67,7 @@
             throw new UncheckedIOException(e);
         }
         if (!canonicalPath.endsWith(File.separator)) {
-            canonicalPath = canonicalPath + "/";
+            canonicalPath = canonicalPath + File.separator;
         }
         m_canonicalRoot = canonicalPath;
     }