Implement various `VirtualKeyboard` methods

Implements:
  VirtualKeyboard.isVisible
  VirtualKeyboard.getXPosition
  VirtualKeyboard.getYPosition
  VirtualKeyboard.getWidth
  VirtualKeyboard.getHeight
  VirtualKeyboard.setVisibilityListener

Also updates the documentation of a couple of classes
Remove superfluous console logging
Add tests for `VirtualKeyboard`
Update # of tests. Correctly reset window height.
Merge branch 'master' of https://github.com/andreasgal/j2me.js into keyboardimpl

Conflicts:
	tests/automation.js
Spacing
Merge pull request #578 from TimAbraldes/keyboardimpl

Implement various `VirtualKeyboard` methods with tests.