typo in buffer protocol docs

respect tristate return values from isinf() functions instead of shadowing them in a "bint" declaration

Add <memory> header to libcpp

* shape calculation was off
* flag macros live in cpython, not cython

[ci skip]

document array module

rename "jedi-typer.py" script to "jedityper.py" to make it importable (which might become interesting at some point)

Experimental support for jedi 0.9.0