Merge branch 'skip-and-todo'

* skip-and-todo:
  Add documentation about todo
  Add a new feature todo
  Add documentation about skip
  Add new feature 'skip'
  Add a wrapper function for cmp_ok
  Change places adding '-' to testname output.
Drop 'echo -n' #2

Drop echo -n for MacOS X.  All echo cannot be removed because
'echo "$@"' is little hard to be replaced by 'printf'.
So I decided to remove only 'echo -n' from my code for now.
Merge branch 'drop-echo-p2' into pu