* yarvcore.c: rename cYarvThread to rb_cThread.
* gc.c: remove YARV_* prefix.
* gc.h: add an include guard and prototype of rb_gc_set_stack_end().
* inits.c: fix to ANSI prototype style and reorder Init_*().
* io.c (pipe_finalize): TODO: comment out last_status.
* process.c, yarvcore.h: fix to use yarv_vm_t#last_status instead of
rb_last_status and make last_status_get() to access $?.
* yarvcore.c (vm_mark): mark yarv_vm_t#last_status.
* ruby.h: add declarations of rb_cISeq and rb_cVM.
* thread.c: move eval_thread.c codes to thread.c and remove yarv_*
function prefix.
* thread.c (thread_start_func_2): use yarv_thread_t#first_func if
it is not null.
* vm.c: fix copyright year.
* yarvcore.c (Init_vm): rename to Init_VM().
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@11631 b2dd03c8-39d4-4d8f-98ff-823fe69b080e