Add the feature to append a binary directly as capsule payload.

Signed-off-by: Yuxin Zheng <yuxin.zheng@intel.com>
Reviewed-by: Chen, Hesheng <hesheng.chen@intel.com> 
Reviewed-by: Liu, Yingke D <Yingke.d.liu@intel.com > 
Reviewed-by: Feng, Bob C <bob.c.feng@intel.com>


git-svn-id: https://svn.code.sf.net/p/edk2-buildtools/code/trunk/BaseTools@2631 c2973edb-eda0-4c78-bc6a-9341b269661f