Add CheckedConsumer[N] and CheckedFunction[N] and add wrapper methods to Unchecked

[lukaseder]

See also: #214 (comment)

[bendem]

Came here to say that. I just had to write

.map(envelopeAndPath -> envelopeAndPath.map2(Function1.from(Unchecked.function(Files::newInputStream))))

Expected to find a method allowing this instead:

.map(envelopeAndPath -> envelopeAndPath.map2(Unchecked.function1(Files::newInputStream)))

or even

.map(envelopeAndPath -> envelopeAndPath.map2Unchecked(Files::newInputStream))

[lukaseder]

Thanks for the feedback, @bendem. This will definitely add value when implemented.

[patrox]

hi @lukaseder & @bendem, could you please have a look at the following PR and let me know if this is what you were after ?

#272

Please note though, that for now this has been done for arity of 1.