Don’t require typing with Python 3.5 and newer

[pluehne]

Python 3.5 and newer ship with built-in typing support. For this reason, there is no need to require the typing package starting from Python 3.5.

On Arch Linux, this requirement caused trouble, because Arch Linux doesn’t provide the typing package anymore, as it is deemed unnecessary now. For this reason, python-miio complains about the missing typing dependency without this adjustment.

[coveralls]

Coverage remained the same at 44.98% when pulling 5077da5 on pluehne:patrick/python-3.5 into 62e82aa on rytilahti:master.

[rytilahti]

Looks good and reasonable, adding that requirement so hastily (and keeping support for py < 3.5) was not properly motivated choice. I think it would actually be fair enough to drop support for py < 3.5 considering Debian stable is also already on it, but let's leave it like that for the time being and merge this. Thanks!