make more comments in the test filler

[winsvega]

in the test fillers there should be added a new section

"_info" : {
"comment" : "Test Desctiption"
}

describing what this test is actually about and how it works. such section will translate this comment into final test by testeth.
additional comments could be done by adding
"//cooment1": "comment"
"//cooment2": "comment"
fields. such fields must have unique id for the .json scheme and would not be translated into the final .json file.

[winsvega]

@qbzzt this is more then just a comment.
having more comments in tests would be nice.

the issue is the whole index we need to have so to be able to tell what is covered and where.