feat: like/dislike, add post, add proposal, add announcement

package-lock.json

package.json

src/App.jsx

src/actions/announcements.js

src/actions/posts.js

src/components/Button.jsx

src/containers/AddAnnouncementForm.jsx

src/containers/AddPostForm.jsx

src/containers/PostFilters.jsx

src/containers/PostsContainer.jsx

src/pages/Home.jsx

src/stores.js

src/utils.js

typings/cf2021.d.ts