Add doxygen support

Signed-off-by: Yen-Chin Lee <coldnew.tw@gmail.com>
Swtich to stroustrup coding style

Signed-off-by: Yen-Chin Lee <coldnew.tw@gmail.com>
move back to google coding style

Signed-off-by: Yen-Chin Lee <coldnew.tw@gmail.com>