Doc: Updated the README file.
Doc: Updated the README file.

-updated "make docs" command information.

Change-Id: Id102998481e15327980221586aef528edb541b6c
Reviewed-by: Jing Bai <ca654a02db76d88a1c19288aa5d4d247688848e6@digia.com>

kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc,kobolabs/qtdoc