(#1526) For consistency sake with func

[baudoliver7]

#1526

• Introduce envelope for Proc, BiFunc, Callable and Runnable
• simplify the code of ProcOf and BiFuncOf etc by extending their envelope

[0crat]

@victornoel/z everybody who has role REV is banned at #1539; I won't be able to assign anyone automatically; consider assigning someone manually (as in §19), or invite more people (as in §51), or remove the job from the scope (as in §14)

[baudoliver7]

@victornoel I submitted a PR but it seems reviewer is missing

[victornoel]

@baudoliver7 I'm receiving the same notifications as you FYI so I'm aware of it :)

I will take a look at it when I have some free time :)

[baudoliver7]

@victornoel Good :)

[victornoel]

@baudoliver7 some comments :)

[baudoliver7]

@victornoel Some changes have been made

[victornoel]

@baudoliver7 great, thx

[victornoel]

@rultor merge

[rultor]

@rultor merge

@victornoel OK, I'll try to merge now. You can check the progress of the merge here

[rultor]

@rultor merge

@victornoel Done! FYI, the full log is here (took me 15min)

[0crat]

Job gh:yegor256/cactoos#1539 is not assigned, can't get performer