tclap: initial add 1.2.1

TCLAP (Templatized C++ Command Line Parser Library ) is a small, flexible
library that provides a simple interface for defining and accessing command
line arguments.

Use the commit of tag tclap-1-2-1-release-final.

Signed-off-by: Ting Liu <b28495@freescale.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>