* implements a Provider singleton, to be used by thirdparty plugins
* exporter: support for thirdparty providers
* splits plugin loading into two steps: discovery and load
1. get a list of all candidate plugins to load for the different paths
2. sort providers before on the rest of them and try to load them
Creating tags on memos looked like "#This is a book title" meaning only "#This" would become a Tag. Replacing spaces with underscore to be more usable so that the following tag would be created "#This_is_a_book_title"
Optimize #11087 :
1. In `isReadyToExport`, check if the ip is set. If not, then the user cannot enable xmnote export.
2. Add author field in highlights.
Export highlights for selected files.
Having a button "Select all files in folder", it is easy to export the whole folder.
So, closes#10402.
To keep even number of buttons, added a feature "Show selected files list". May be useful to check selections before an operation. Just a sorted list, no titlebar or popup menu, tapping a file jumps to its folder.
This allows interoperability between different readers who want to
import highlights on different devices/file systems. All that is
needed then to import highlights is to match the local books and
their path based on the checksum.
Basically:
* Use `extend` for class definitions
* Use `new` for object instantiations
That includes some minor code cleanups along the way:
* Updated `Widget`'s docs to make the semantics clearer.
* Removed `should_restrict_JIT` (it's been dead code since https://github.com/koreader/android-luajit-launcher/pull/283)
* Minor refactoring of LuaSettings/LuaData/LuaDefaults/DocSettings to behave (mostly, they are instantiated via `open` instead of `new`) like everything else and handle inheritance properly (i.e., DocSettings is now a proper LuaSettings subclass).
* Default to `WidgetContainer` instead of `InputContainer` for stuff that doesn't actually setup key/gesture events.
* Ditto for explicit `*Listener` only classes, make sure they're based on `EventListener` instead of something uselessly fancier.
* Unless absolutely necessary, do not store references in class objects, ever; only values. Instead, always store references in instances, to avoid both sneaky inheritance issues, and sneaky GC pinning of stale references.
* ReaderUI: Fix one such issue with its `active_widgets` array, with critical implications, as it essentially pinned *all* of ReaderUI's modules, including their reference to the `Document` instance (i.e., that was a big-ass leak).
* Terminal: Make sure the shell is killed on plugin teardown.
* InputText: Fix Home/End/Del physical keys to behave sensibly.
* InputContainer/WidgetContainer: If necessary, compute self.dimen at paintTo time (previously, only InputContainers did, which might have had something to do with random widgets unconcerned about input using it as a baseclass instead of WidgetContainer...).
* OverlapGroup: Compute self.dimen at *init* time, because for some reason it needs to do that, but do it directly in OverlapGroup instead of going through a weird WidgetContainer method that it was the sole user of.
* ReaderCropping: Under no circumstances should a Document instance member (here, self.bbox) risk being `nil`ed!
* Kobo: Minor code cleanups.
