EclipseHelper: handle spaces in the directory path

Even if the relative paths in class path cannot have spaces, the
directories making up the class path can very well contain spaces
somewhere along the lines.

By using the FileUtils to convert from a file: URL to a File, we
handle spaces and all kinds of funny characters in the directory
names at the same time.

Pointed out by Christian Dietz.

Incidentally, this also fixes *another* problem Christian pointed
out: on Windows, the file: URLs cannot be turned into proper
paths by stripping the "file:" prefix because the URLs start with
a slash to indicate absolute paths, then continue with the DOS
style drive letter and a colon because that is what Windows calls
an absolute path.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

src/main/java/org/scijava/annotations/EclipseHelper.java

@@ -42,6 +42,8 @@
 import java.util.jar.JarFile;
 import java.util.jar.Manifest;
 
+import org.scijava.util.FileUtils;
+
 /**
  * Helps Eclipse's lack of support for annotation processing in incremental
  * build mode.
@@ -198,7 +200,7 @@ private void maybeIndex(final URL url, final ClassLoader loader) {
 			}
 			return;
 		}
-		File directory = new File(path);
+		File directory = FileUtils.urlToFile(url);
 		if (!directory.isDirectory()) {
 			return;
 		}