Test-steps

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* add lesson 5 example for checks batch argument
* fix issue 12: multiple options for checks error

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* add passdesc (-p) and faildesc (-f) option for step/check function
* add check/checks as alias for step/steps
* add the return values for step and steps function
* add a batch parameter to steps/checks function

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* added debug info logging
* added -e and -w option for exception and warning
* add a mechanism for new option insertion
* enhanced the ok function

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This is a fairly complete list of v0.1, which can
serve as a reference for test engineers.

* automatically log test cases and steps
* implemented general operators and corresponding functions, including::
eq, ne, gt, lt, ge, le, match, unmatch
* implemented the framework for adding new operators and functions
* implemented step/steps/s functions, which can be used in some test frameworks