Resolve "Websocket error propagation lacks usability"

[btschwertfeger]

Summary

• Adding an enum that communicates the websocket connection states
• Fix typo

Closes #352

[codecov]

Codecov Report

Attention: Patch coverage is 77.46479% with 16 lines in your changes missing coverage. Please review.

Project coverage is 86.11%. Comparing base (2c6194c) to head (7536ef7).

Files with missing lines	Patch %	Lines
src/kraken/spot/websocket/connectors.py	70.83%	7 Missing ⚠️
src/kraken/futures/websocket/__init__.py	70.00%	6 Missing ⚠️
src/kraken/spot/websocket/__init__.py	82.35%	3 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #363   +/-   ##
=======================================
  Coverage   86.10%   86.11%           
=======================================
  Files          25       25           
  Lines        2131     2168   +37     
=======================================
+ Hits         1835     1867   +32     
- Misses        296      301    +5     

Flag	Coverage Δ
unittests	86.11% <77.46%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/kraken/spot/funding.py	45.83% <ø> (ø)
src/kraken/utils/utils.py	91.30% <100.00%> (+6.68%)	⬆️
src/kraken/spot/websocket/__init__.py	88.88% <82.35%> (-2.03%)	⬇️
src/kraken/futures/websocket/__init__.py	84.61% <70.00%> (+0.22%)	⬆️
src/kraken/spot/websocket/connectors.py	87.15% <70.83%> (+0.09%)	⬆️