[Py] add find algorithms
[Py] add sort algorithms
[Py] support Markdown-style doc
[Py] add chain() in loop techniques
[Py] Change loop techniques to executable
[Py] merge iterator into loop techniques
[Py] merge generator into loop techniques
[Py] add filter to loop techniques
[Py] add iterator/generator slicing into loop techniques
[Py] add permutations & combinations into loop techniques
[Py] update loop techniques with doctest
[Py] add chain() reference implementation to loop techniques
[Py] add text pattern