Epic Branch: v2 release

[hannahhoward]

Goals

Given the number of expected breaking changes, it's very much neccesary to setup a v2 release. This is an epic branch to merge big refactor PRs to until we get to merging to master for a v2 release.

[codecov-commenter]

Codecov Report

Merging #323 (aad2287) into master (4a865de) will increase coverage by 0.76%. The diff coverage is 68.54%.

@@            Coverage Diff             @@
##           master     #323      +/-   ##
==========================================
+ Coverage   65.97%   66.74%   +0.76%     
==========================================
  Files          29       25       -4     
  Lines        3436     2556     -880     
==========================================
- Hits         2267     1706     -561     
+ Misses        816      674     -142     
+ Partials      353      176     -177     

Impacted Files	Coverage Δ
tracing/tracing.go	93.75% <ø> (ø)
transport/graphsync/hooks.go	67.45% <ø> (ø)
transport/graphsync/receiver.go	53.39% <ø> (ø)
transport/graphsync/utils.go	96.15% <ø> (ø)
transport/helpers/network/interface.go	60.00% <ø> (ø)
transport/helpers/network/libp2p_impl.go	64.62% <ø> (ø)
message/message1_1prime/transfer_message.go	26.31% <36.36%> (+6.31%)	:arrow_up:
message/message1_1prime/message.go	57.34% <45.83%> (+2.94%)	:arrow_up:
impl/events.go	40.00% <48.35%> (-37.09%)	:arrow_down:
registry/registry.go	65.21% <57.14%> (-9.79%)	:arrow_down:
... and 24 more