...from most rtl/bootstrap.h functions.  They are effectively only called from
C++ code (there is no plain C UNO binding), so it should be fine to let std
exceptions (like bad_alloc or length_error) propagate from their implementations
to call sites.

(The exception is rtl_bootstrap_args_close, which is typically called from C++
dtors, so should not throw anyway.)

This would strictly speaking be an [API CHANGE], but it should make no practical
difference whether a process terminates abruptly because an exception cannot
pass through a SAL_THROW_EXTERN_C() nothrow specification or because legacy
client code does not expect exceptions to be thrown from functions from which
SAL_THROW_EXTERN_C() has now been removed.

Change-Id: I08e8479e9c5731e46021aadd6a725c1793024d10