Themify lader

[dewanshDT]

Fixes #2131

Changes:
added themify to loader-container in `_loader.scss'. check the commits for more details. Simple fix, now it works fine.

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123