reformat code samples in doc to 2 spaces
reformat code samples in doc to 2 spaces

dynamid/golo-lang-insa-citilab-historical-reference,titimoby/golo-lang,titimoby/golo-lang,dynamid/golo-lang-insa-citilab-historical-reference,smarr/golo-lang,smarr/golo-lang,dynamid/golo-lang-insa-citilab-historical-reference