Prepare MTCP header in threadlist.cpp.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2822 ba6dc0ae-232f-0410-883f-9ebac64fc565
MTCP: Move code from restore_libc to mtcp_header

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2823 ba6dc0ae-232f-0410-883f-9ebac64fc565
MTCP: Better definition of myinfo_gs.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2824 ba6dc0ae-232f-0410-883f-9ebac64fc565
MTCP: Add tls_tid_offset, etc to mtcp header.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2825 ba6dc0ae-232f-0410-883f-9ebac64fc565
Move tls_[gs]et_thread_area to mtcp/tlsutil.h

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2826 ba6dc0ae-232f-0410-883f-9ebac64fc565
MTCP: restore libc in mtcp_restart itself.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2827 ba6dc0ae-232f-0410-883f-9ebac64fc565