Add code check target to build system

[mbrandenburger]

formatting check, referring to golinter from fabric; potentially separate comment which auto-indents potentially also clangformat related target for C code

update READMEs to match above changes ..

This is needed for CI as well.

This links back to #38

• code check for GO

• code check for c/cpp code checks for c/cpp #76

• spellchecker (optional)

• license Add missing license identifier #73

[mbrandenburger]

#61 adds code checks for go.

[mbrandenburger]

#84 adds code checks for cpp