Shifting the script tags from body to head tag

[rajneesh069]

For clean index.html so that anyone who starts contributing or looking into the project can instantly know what scripts have been used, we can move the script tags into the head tag and add the "defer" attribute into them, which will help us achieve the same but inside the head tag, resulting in cleaner code.
Before :

After :

I'd like to work on this issue if it gets approved.

[nisha-laur]

@rajneesh069 you may go ahead with this .

[rajneesh069]

@nisha-laur I've already tried the whole cleaner folder structure twice but you'll have to merge the PRs beforehand, because each time someone commits a new change in the repo, I'll have to make the changes again, and merge conflicts will arise again and again. After the folder structure is changes everyone can pull the changes and make the relevant changes, that's why I am unable to make the proposed changes. Please look into it.