Sigmon 204 mkdocs webeos

Context

• Project(s) README(s) link(s)
• Story reminder: https://its.cern.ch/jira/browse/SIGMON-204
• Task details

• Moved the Mkdocs configuration to the main api repo
• update the API generation doc

What was done

• keypoints of the implementation / code changes

• Moved all the files from sigmon-docs repo to api
• update the gitlab-ci to generate documentation and api documentation using pages
• generate URI with branch name

Review objectives

• assessment of code functionality
• assessment of code quality
• identifying potential refactorings / logic common to other projects
• knowledge sharing