try to support requestHelper , but test failed now
fix useDefault bug, now build pass
remove console.log
update schema for yqlConfig
refine schema and steps
add more tests, fix ATask.validateRequests
refine test and schema
refine test (still 1 error)
reorg schemas (now we have common definition)
fix schema typo (now still 2 failed test)
another typo
draft4 do not support 'extends' , move to allOf
fix schemas , now follow draft 4 100%
refine schema and tests
refine schema
refine schema. handle more on yqlConfig