Make error usable earlier

error (and other exception-throwing functions) are callable from the
first line of captured_main, but the exception printing code will
crash if called before the first call to set_width.  This commit makes
the exception printing code usable from the moment gdb_stderr is set
up.

gdb/
2014-08-05  Gary Benson  <gbenson@redhat.com>

	* exceptions.c (print_flush): Protect calls to
	target_terminal_ours and wrap_here.
Cope with early(ier) warnings too
List of calls to exit
False positives and other rubbish
Space the list
Replace two random error-exit things
Document
Replace another
Documentation
Replace another
Documentation
Documentation