Join server channel using NIPs instead of ServerID

[renatomassaro]

Depends on #267

• [x] Websocket Channel State, mapping NIPs to ServerID
  • [x] Interface
  • [x] Tests
  • [x] Docs
• [x] Modify Server Joinable
• [x] Modify tests

Closes #273

TODO:

• [x] Timer for ChannelState server garbage collector
• [x] Automatically grab next counter unless explicitly set during join
• [x] Typespecs on ChannelState

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Incidental:

• DevTools.ETS
• Changed Notificable.whom_to_notify return format

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This change is 

#

[renatomassaro]

Reviewed 37 of 37 files at r1. Review status: all files reviewed at latest revision, 1 unresolved discussion.

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lib/server/websocket/channel/server.ex, line 30 at r1 (raw file):

  "server:<network_id>@<destination_ip>[#<counter>]"

  [#<counter>] denotes optional argument. If omitted, counter=0 will be assumed.

Enhance doc

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Comments from Reviewable

[sourcelevel-bot[bot]]

Ebert has finished reviewing this Pull Request and has found:

• 1 possible new issue (including those that may have been commented here).

You can see more details about this review at https://ebertapp.io/github/HackerExperience/Helix/pulls/276.

[renatomassaro]

Reviewed 1 of 1 files at r2. Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable