staging/ktap: minor typo update on Kconfig

Use "ktap" instead of "KTAP" in Kconfig, also add
tutorial link in Kconfig.

Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@gmail.com>
staging/ktap: delete doc/presentation

Those slides will move to website(www.ktap.org),
delete it in git tree.

Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@gmail.com>