add docstrings for kits.map
add docstrings for kits.seq
fix testcase: test->timestamp---with-specified-format
Merge pull request #3 from xumingming/fix-ts-case

fix testcase: test->timestamp---with-specified-format
Merge pull request #4 from xumingming/map

add docstrings for kits.map
Merge pull request #5 from xumingming/seq

add docstrings for kits.seq