Changed default port. Added logic to start app in browser

[adilahmed31]

• Updated installation steps for Ubuntu (Verified on Ubuntu 20.04). Changed port number in instructions.
• Changed port number from 5000 to 6200.
• Added logic to start browser automatically (disabled when running in DEBUG mode). It can be made to work in debug mode by simply disabling Flask's auto reloader by setting app.run(use_reloader=False) . Otherwise the browser tab is opened twice if run in debug mode.

Resolves #19

[adilahmed31]

The new port worked on macOS but the browser did not open for me either. Let's solve that before merging but otherwise the changes are good

The browser open is disabled when run in DEBUG mode, which is the default currently. Flask runs an auto reloader in debug mode, which is used to automatically relaunch the app when any code change occurs while the app is running. This causes the browser tab to open twice in debug mode so i disabled it.

If we disable this auto reload, it should work pretty smoothly. If we want to keep it, there are some hacky solutions / workarounds. Are we okay with disabling the auto reload?

[grantv9]

The browser open is disabled when run in DEBUG mode, which is the default currently

I wasn't running in debug mode (aka ran TEST=0 ./isdi), and the browser didn't open for some reason.

Are we okay with disabling the auto reload?

Given that test mode is being removed in #32, I think we can ignore the situation where the browser tab is opened twice. Ultimately the port functionality works, so I'm fine approving this.

[adilahmed31]

The new port works as expected. I'm not seeing the browser open either, but I'm fine approving the changes

Great! I had put in a one line flag to disable the browser open in some modes. I've removed it and it should work perfectly now irrespective of which mode it's run in