Changes

* For a simple virtual keyboard action (send a character and key events w/ each user action), use <code>sendKey()</code>. TODO: should we allow backspace key to be sent from the method? If not, how do send these non-printable characters and it's effect with key events?* For backspace key, spellcheck, autocomplete etc, use surrounding text methods.* For cursor moment helper features, use <code>setSelectionRange()</code> and related attributes.* For Asian IMEs that sends characters and composition along with the composition events, use <code>setComposition()</code> and <code>endComposition()</code>.