Add ci by GitHub actions#60

[yosukesan]

If you merge this patch. CI, using Github actions, is going to be enabled on main branch automatically. In my test, unit test successfully terminated on win, mac and linux(Ubuntu). see below for detail. https://github.com/yosukesan/python-xbrl/actions/runs/3775233998

Since, initially test failed due to too old dependencies. I updated requirements.txt as well. This change includes RP https://github.com/greedo/python-xbrl/pull/57 and will be conflict.