Remove FD_CLOEXEC flag from protected fds.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2629 ba6dc0ae-232f-0410-883f-9ebac64fc565
Jalib:: minor cleanup.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2630 ba6dc0ae-232f-0410-883f-9ebac64fc565
Remove PID_VIRT check from autotest.py.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2631 ba6dc0ae-232f-0410-883f-9ebac64fc565
Updated dmtcp_launch plugin list.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2632 ba6dc0ae-232f-0410-883f-9ebac64fc565