Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
* thread.c (add_thread_silent): Renamed
from add_thread.
(print_thread_events): New variable definition.
(show_print_thread_events): New function.
(_initialize_thread): Add "set print thread-events" and
"show print thread-events" commands.
(add_thread): Announce new thread.
* gdbthread.h (add_thread_silent): Declare.
(print_thread_events): New variable declaration.
* inf-ttrace.c (inf_ttrace_wait): Don't
inform about new thread, as add_thread is always
called too, and will take care of that.
* infrun.c (handle_inferior_event): Likewise.
* procfs.c (procfs_wait): Likewise.
* remote.c (remote_currthread): Likewise.
* sol-thread.c (sol_thread_wait): Likewise.
* win32-nat.c (get_win32_debug_event): Likewise.
* linux-thread-db.c (attach_thread): Likewise.
Remove the verbose parameter.
(check_event): Make detach_thread be verbose
only if print_thread_events is set.
* linux-nat.c (lin_lwp_attach_lwp): Don't inform
about new thread. This is called only from
linux-thread-db.c:attach_thread, which will take care.
Remove the verbose parameter.
* linux-nat.h (lin_lwp_attach_lwp): Adjust prototype.
