refactor: use gorilla mux router

.vscode/launch.json

configs/tokenskey.json

go.mod

go.sum

internal/auth/auth.go

internal/database/database.go

internal/monthlyNews/monthlyNews.go

internal/rootmux/rootmux.go

internal/rootmux/rootmux_test.go

main.go

web/components/login/login.js

web/components/navbar/navbar.js

web/components/post/post.js

web/main.js

web/services/auth/auth.js

web/services/common/delete.js

web/services/common/errors.js

web/services/messages/messages.js