Deprecate the blocking parameter of File, Socket and IO::FileDescriptor constructors

[ysbaddaden]

The final patch to the blocking behavior rework. Each event loop configures the system file descriptor or handle as per its internal requirement, and we shall deprecate the blocking argument.

Extracted from #15924. Follow up to #15804, #15754, #15753, #15750, #15930 and #15977. Depends on #15999 and #16012 for the deprecations to be visible.

Parser support for annotations on def parameters was only added in #12044 for Crystal 1.5.

[straight-shoota]

The version flags are annoying, but I suppose there's no way around that.

[ysbaddaden]

At some point we might release a 2.0 that would allow us to drop these in a 2.x release, so we can build 1.0 -> 2.0 -> 2.x. Maybe.

[ysbaddaden]

Or release patched versions of 1.0 -> 1.4 where the parser will skip over argument annotations?

[straight-shoota]

Alternatively, we could break forward compatibility for building a 1.x compiler with a compiler < 1.5.
But this requires more consideration about the implications and exact implementation details (related: #12937).

[Blacksmoke16]

This PR seems a bit problematic related to its deprecation warnings. If I have a file with puts "foo" and run it on latest commit in master I get:

$ ccrystal test.cr
Using compiled compiler at /home/george/dev/git/crystal/.build/crystal
In /home/george/dev/git/crystal/src/file.cr:525:3

 525 | {% begin %}
       ^
Warning: expanding macro


There was a problem expanding macro 'macro_140154605514400'

Called macro defined in /home/george/dev/git/crystal/src/file.cr:525:3

 525 | {% begin %}

Which expanded to:

    1 |
    2 |   def self.open(filename : Path | String, mode = "r", perm = DEFAULT_CREATE_PERMISSIONS, encoding = nil, invalid = nil,  @[Deprecated]  blocking = nil, &)
 >  3 |     file = new filename, mode, perm, encoding, invalid, blocking
    4 |     begin
    5 |       yield file
    6 |     ensure
    7 |       file.close
    8 |     end
    9 |   end
   10 |
Warning: Deprecated argument blocking.

A total of 1 warnings were found.
foo

I feel like I shouldn't be getting warned about something in the stdlib that I have no control over fixing.