Fix Java Meterpreter Symlink Handling on Windows

[zeroSteiner]

This fixes issues in how the Java Meterpreter handles links and junctions when running on Windows. This issue arose when these tests failed due to the new addition of tests in rapid7/metasploit-framework#19554.

Along the way the following additional changes were made:

• An issue with process execution was fixed whereby the subprocess did not have its working directory properly set.
• pom.xml compatibility checks for Java 6 were updated to use javascript to select versioned files, so all files lacking a version and marked for version 1-6 are included. This means new versioned files can be added in the future without troubleshooting and updating this pom.xml.
• Added version detection for Java 7 and 8.

For testing:

• Grab the changes from PR 19554.
• Start a Java Meterpreter session on a Windows host, make sure Java is version 8 or newer. Older versions will still fail and there's not much that can be done about that. Java 8 was released in 2014.
• Run the tests and see them all work

[smcintyre-r7]

This PR should be landed because the tests are passing in rapid7/metasploit-framework. Once this is landed, the Metasploit side of things should be laned after the last commit updating the testing definition is reverted:

rapid7/metasploit-framework@6274d04