Replace the short video with an animated vector image that shows the
swipe gesture.
This is much lighter and reliable than the mp4 video, which failed to
play on many devices.
Source for the image of the key is in inkscape SVG format in srcs/res
and is converted to an android drawable when needed. The swipe animation
is hand-written.
This adds the clipboard pane, which allows to save an arbitrary number of
clipboards and to paste them later. The key can be disabled in settings.
Checking the "Recently copied text" checkbox will cause the keyboard to keep a
temporary history of copied text. This history can only contain 3 elements
which expire after 5 minutes.
If this is unchecked, no history is collected.
History entries can be pinned into the persisted list of pins.
This was a half-finished feature:
- Dangerous when typing passwords
- Caused crash on some devices
- Ugly (on its own but also blinking when sliding and not fixed in size)
