Autoyast: "add_crashkernel_param" will be set by using autoinst.xml
evaluate default add_crashkernel_param if it is not set in autoinst.xml
packaging
Merge pull request #21 from yast/review_140807_set_add_crashkernel_param_in_autoyast

[Review] Request from 'schubi2' @ 'yast/yast-kdump/review_140807_set_add_crashkernel_param_in_autoyast'