* LuaSettings/DocSettings: Updated readSetting API to allow proper initialization to default.
Use it to initialize tables, e.g., fixing corner-cases in readerFooter that could prevent settings from being saved.
(Fixes an issue reported on Gitter).
* LuaSettings/DocSettings: Add simpler API than the the flip* ones to toggle boolean settings.
* Update LuaSettings/DocSettigns usage throughout the codebase to use the dedicated boolean methods wher appropriate, and clean up some of the more mind-bending uses.
* FileChooser: Implement an extended default exclusion list (fix#2360)
* ScreenSaver: Refactor to avoid the pile of kludges this was threatening to become. Code should be easier to follow and use, and fallbacks now behave as expected (fix#4418).
* Top menu & bottom menu tapzones are now full-width, thanks to the now sane override system.
* A separate, extra tapzone was also created for each of them to provide a taller, but narrower tapzone extension (one that doesn't clash with the prev/next tapzones).
* The footer tapzone was made much taller.
Have ReaderBack be the sole handler of onBack.
Add 4 mutually exclusive options for the Back key,
to avoid ReaderLink and ReaderBack location stacks
from interfering (ReaderBack's stack being always a
superset of ReaderLink's stack).
So, remove "Enable back history", which is replaced
by Back option "Go to previous read page".
Fix a few possible crashes and inconsistencies (when
zoom, scroll or reflow have changed) with ReaderPaging
and ReaderView when restoring previous page/view.
Follow up to b90f6db8: allow specifying an other
value for tap interval when the keyboard is shown
(a good value for tap interval on reader and UI
elements might be too long on the keyboard, and
prevent typing fast).