:lipstick: Replace deprecated methods.

- :racehorse: Important because Deprecation Cop's stack slows down execution dramatically.
- Replace editor.getCursor() with editor.getLastCursor().
- Replace editor.moveCursorRight() with editor.moveRight().
- Replace editor.moveCursorLeft() with editor.moveLeft().
- Replace editor.moveCursorToBeginningOfNextWord() with editor.moveToBeginningOfNextWord().
- Replace editor.getSelection() with editor.getLastSelection().
- Replace editor.lineLengthForBufferRow(row) -> editor.lineTextForBufferRow(row).length.