Add Sub module
--------------
git submodule add https://github.com/thilinah/isotope-core.git src

Remove Sub Module
-----------------
git submodule deinit src
git rm src
git rm --cached src
rm -rf .git/modules/src

//TODO - Add other modules also

Errors while pushing code for sub module

git remote set-url origin https://<user>@github.com/thilinah/isotope-core.git

<user> must have rights to push code to the repo