...in an attempt to reduce usage of type-unsafe

  void const * css::uno::Any::getValue()

These new functions are often more convenient to use than the existing ">>=" and
Any::get<T>.  Note how they are careful to provide a pointer directly into the
given Any, instead of creating temporaries.

As an example, replaced most calls of getValue across xmloff:

* Cases that first check for a specific type (via getValueType etc.) and then
  call getValue can instead call tryGet.  (But beware that tryGet supports some
  conversions, which a check for a specific type may have missed---either
  intentionally or by accident.  Also beware the somewhat common idiom of
  checking for TypeClass_ENUM and then using getValue to obtain a sal_Int32;
  this cannot be replaced with a call to tryGet.)

* Cases that seem confident that the Any is of the correct type when calling
  getValue (but apparently are confident due to some higher-layer protocol, as
  the surrounding code does not do any checking via getValueType or similar) can
  instead call doGet.  It throws an exception if it turns out the confidence
  wasn't warranted.  (Many of the existing calls that directly dereferenced the
  return value of getValue as sal_Bool look suspicious, in that the author might
  have thought the given code would also cover a VOID Any---which technically it
  even would have happened to do.  If any RuntimeExceptions thrown from these
  doGet calls start to crop up, these changes need to be revisited.  Some may
  even be rewritten as uses of ">>=".  But at least "make check" did not show
  any such problems.  Also note that casting the value obtained from getValue to
  any css::uno::Reference<X> with X being anything but the base
  css::uno::XInterface was always prone to producing a bad pointer, in case the
  interface actually stored in the Any derived from X via multiple inheritance.)

* Should there ever be cases where an Any is known to be of the requested type,
  some additional forceGet could be introduced (which would assert instead of
  throwing an exception).

Change-Id: I2d8739e86314eff73abfcafe01d806f5bc5c34db