FILE: Create creat() and creat64() wrappers.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2835 ba6dc0ae-232f-0410-883f-9ebac64fc565
Fixes for syscall-tester test.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2836 ba6dc0ae-232f-0410-883f-9ebac64fc565
syscall-tester: Use 'xc' instead of 'c' for ckpt

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2837 ba6dc0ae-232f-0410-883f-9ebac64fc565
Added a TODO item.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2838 ba6dc0ae-232f-0410-883f-9ebac64fc565