move packages related to v0.1.0 to the plugins/v010-adapter

[Iceber]

issue: #153

• Delete ./examples and ./skel. If users really need them, they can use the NRI package from the old tag.
• Move ./README-0.1.0.md, ./types, and ./client-go to ./plugins/v010-adapter.
• Removed the Background section from the README.md. It primarily described the differences compared to NRI v0.1.0.

[klihub]

Should we still keep a revisited short 'Background' or 'Introduction' section which briefly tells in a few sentences what NRI is ?

[klihub]

Well, we have the Goal section. Maybe that's good enough then.

[klihub]

LGTM.

[mikebrow]

looking good just a few more changes I think

[mikebrow]

leave a short description and a hyper link reference to the new 0.1.0/readme

e.g.
original v0.1.0 CLI invoke style version of NRI has been moved
v0.1.0 docs

[mikebrow]

I'd leave the background section in, remove the first paragraph .. move the second v0.1.0 paragraph to the new 0.1.0 readme.. and revise the 3rd paragraph with a more forward presence.. vs the change to now perspective.

[Iceber]

What do you think of adjusting the third paragraph of the reservation to read as follows:

## Background
Plugins in NRI are daemon-like entities. A single instance of a plugin is responsible for handling the full stream of NRI events and requests. A unix-domain socket is used as the transport for communication. 

NRI is defined as a formal, protobuf-based 'NRI plugin protocol' which is compiled into ttRPC bindings. This should result in improved communication efficiency with lower per-message overhead, and enable straightforward implementation of stateful NRI plugins.

Since the Background section no longer contains content related to 0.1.0, the section name seems a bit odd. It reads more like a description of the Plugin.
Do you think it would be better to either make it a subsection within the Goal section or just move it directly into the Goal section?
eg.

## Goal
....

### Plugins
Plugins in NRI are daemon-like entities. A single instance of a plugin is responsible for handling the full stream of NRI events and requests. A unix-domain socket is used as the transport for communication. 
...

[mikebrow]

both options work for me :-)

[samuelkarp]

@Iceber Do you plan to address @mikebrow's comments?

[Iceber]

@mikebrow @samuelkarp I am sorry for not handling it in a timely manner.

I have now updated it, please take a look.

[mikebrow]

LGTM

[samuelkarp]

FYI I opened #176 to revert this; turns out there's still some usage of this inside containerd that we'll probably want to figure out a deprecation/removal path for before actually removing the old NRI client code.