Added flow stuff

.flowconfig

.gitignore

.gitlab-ci.yml

client/.npmrc

client/package-lock.json

client/package.json

client/src/.flowconfig

client/src/Article.js

client/src/ArticleWidgets.js

client/src/CommentWidgets.js

client/src/index.js

client/src/stores.js

client/tests/articleStore.test.js

flow-typed/npm/axios_v0.19.x.js

flow-typed/npm/cross-env_vx.x.x.js

flow-typed/npm/flow-bin_v0.x.x.js

flow-typed/npm/history_v4.10.x.js

flow-typed/npm/jest_v24.x.x.js

flow-typed/npm/mysql_v2.x.x.js

flow-typed/npm/react-bootstrap_vx.x.x.js