Resolve "add a contribute section"

Closes #30

See merge request fusiondirectory/user-manual!159

(cherry picked from commit 55424823)

104ed297  feat(bugreport) add a section how to report a bug from user point of view

Resolve "code of conduct"

Closes #84

See merge request fusiondirectory/user-manual!146

(cherry picked from commit df79ee64)

60163519  feat(code-of-conduct) code of conduct