Update dependency URLs in README.md
The existing URL for args4j 404s.  The page at the existing URL for JUnit says it's deprecated.  I've replaced them with the correct ones.
Closes
@@ -231,7 +231,7 @@ system have been added.</td>
<table>
<tr>
<td>URL</td>
- <td>https://args4j.dev.java.net/</td>
+ <td>http://args4j.kohsuke.org/</td>
</tr>
<tr>
@@ -319,7 +319,7 @@ options/arguments in your CUI application.</td>
<table>
<tr>
<td>URL</td>
- <td>https://sourceforge.net/projects/junit/</td>
+ <td>http://junit.org/junit4/</td>
</tr>
<tr>
