refactor APIProvider to NodeProvider

[evan-forbes]

Description

This simple PR refactors APIProvider to NodeProvider, where it now would return a full *core.IPFS object instead of only the DAG portion.

Closes: #399

[codecov-commenter]

Codecov Report

Merging #400 (c8f6f93) into master (b7fe560) will decrease coverage by 0.08%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master     #400      +/-   ##
==========================================
- Coverage   61.81%   61.73%   -0.09%     
==========================================
  Files         262      262              
  Lines       22981    22979       -2     
==========================================
- Hits        14206    14185      -21     
- Misses       7273     7284      +11     
- Partials     1502     1510       +8     

Impacted Files	Coverage Δ
cmd/tendermint/commands/light.go	18.12% <0.00%> (+0.22%)	⬆️
light/client.go	64.34% <0.00%> (ø)
node/node.go	55.92% <100.00%> (ø)
privval/signer_listener_endpoint.go	80.00% <0.00%> (-7.06%)	⬇️
privval/socket_listeners.go	78.72% <0.00%> (-4.26%)	⬇️
privval/secret_connection.go	72.68% <0.00%> (-3.61%)	⬇️
libs/clist/clist.go	63.74% <0.00%> (-3.51%)	⬇️
blockchain/v0/reactor.go	63.06% <0.00%> (-2.26%)	⬇️
consensus/replay.go	70.53% <0.00%> (-0.83%)	⬇️
p2p/switch.go	65.43% <0.00%> (-0.62%)	⬇️
... and 7 more

[liamsi]

Just noting here before restarting CI; these 2 tests look highly unrelated:

?   	github.com/lazyledger/lazyledger-core/libs/fail	[no test files]
--- FAIL: TestWriter (0.48s)
    io_test.go:150: w.Status(0)
        expected: {2021-06-11 21:51:01.14 +0000 UTC 80 4 200 200 200 200 20 400ms 0s 100ms 80.000% true}
        got     : {2021-06-11 21:51:01.14 +0000 UTC 80 4 200 200 200 200 20 400ms 20ms 100ms 80.000% true}
FAIL

--- FAIL: TestTransportMultiplexAcceptNonBlocking (0.23s)
    transport_test.go:349: auth failure: conn.ID (8a87dfa34aa525256f40129427284a32109d8d8f) NodeInfo.ID (fd2d6e0caf965a8118c82109571daa885026e54c) mismatch
FAIL

Note: the first one is from libs/flowrate which isn't even used in tendermint (and hence was removed there: https://github.com/tendermint/tendermint/tree/master/libs) NVM, it's used in p2p/connection and it was jujst moved to internal: https://github.com/tendermint/tendermint/tree/master/internal/libs/flowrate

And the 2nd has nothing to do with any change here.

[liamsi]

Thanks @evan-forbes. Looks great!

[Wondertan]

Bellissimo!!!