Implement hot reloading for golang backend

[dkumiszhan]

Currently, hot reloading is only available for svelte frontend. Ideally we can run golang backend with svelte frontend reloading both. To support that we need the following:

• google authentication not working on localhost:8080
• live reload go backend with air or something similar
• make svelte frontend fetch data from golang backend on different ports. I partially implemented that in Implement myqueries page using routify #77.

[iamabhi747]

google authentication is failing due to CORS policy on /login handler

changing this line in routes.go
r.POST("/login", cs.loginHandler)
to this
r.POST("/login", handlers.CorsMiddleware(cs.loginHandler))