debug info should go to stdout instead of stderr

[ubogdan]

Describe the PR
add support to set up a logger for the parser. The default one should write to stdout instead of stderr.

Relation issue
#929

Additional context
NONE

[codecov]

Codecov Report

Merging #990 (c49b897) into master (642f320) will increase coverage by 0.61%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #990      +/-   ##
==========================================
+ Coverage   92.57%   93.19%   +0.61%     
==========================================
  Files           8        7       -1     
  Lines        1925     1924       -1     
==========================================
+ Hits         1782     1793      +11     
+ Misses         80       73       -7     
+ Partials       63       58       -5     

Impacted Files	Coverage Δ
operation.go	95.10% <100.00%> (+0.84%)	⬆️
parser.go	93.35% <100.00%> (+0.79%)	⬆️

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[ubogdan]

a CR will be much appreciated. 10x

[ubogdan]

@easonlin404 should we forget about this feature?

[ubogdan]

@sdghchj can you please give me a hand with a CR.

[sdghchj]

LGTM

[ubogdan]

Thank you.