Make PagedTiffHandler extend TransformationalImageHandler

This will allow PagedTiffHandler to use VipsScaler, and
reduce some duplicated code.

This change also removes PagedTiffHandler's built in
support for VIPS, since we're going to want to use
VipsScaler, and not much point keeping two methods
of doing the same thing around.

Escaping for image magick command was also made more robust.

This change also affects some of the error handling code
as, using the core classes changes the order normaliseParams
is called. One test was changed as having a srcWidth of 0
is now caught in an earlier validation step. Various methods
that do lastPage/firstPage checks also now pretend its a single
page document instead of returning false when they don't know,
since almost none of the callers were checking for false when
calling those functions. (False would have become 0 when cast
to an integer, which would have been converted to 1 by
ImageHandler::normaliseParams anyways, so this shouldn't change
anything).

This change requires Id3a8b25a598942. In order to scale very
large files, it will require Ifdcb93ea9198f due to quirks in
how vips works.

Bug: 52045
Change-Id: I1b9a77a4a56eeb6535fa46d30b2051841389951c