This should be suitable for laying out text objects with word-wrap,
where each view is a "word" or break between "words". This should be
useful for any other objects that could benefit from similar layout
rules. All eight flows are supported left-right-top-down (English and
most European languages), right-left-top-down (Arabic and similar),
top-down-right-left (Chinese, Japanese, Korean), top-down-left-right,
as well as bottom-up variants of those four.
More work is needed for support of things like views being centered on
the flow line rather than on one edge (depends on flow direction),
offset views, and others. Suppression of "spaces" at the beginning of a
line is supported but not tested.
view_new sets the geometry, but any setgeometry that need a valid data
pointer would get null. It might be better to always have the data
pointer, but I didn't feel like doing such a change at this stage as
there are quite a lot of calls to view_new. Thus view_new_data which
sets the data pointer before calling setgeometry.
And use it for hud_scoreboard_gravity. Putting the enum def in view made
the most sense as view does own the base type and the enum is likely to
be by useful for other settings.
One moves and resizes the view in one operation as a bit of an
optimization as moving and resizing both update any child views, and
this does only one update.
The other sets the gravity and updates any child views as their
absolute positions would change as well as the updated view's absolute
position.