[Docs] Add src/ alias as withvoid/melting-pot in demos

[adeelibr]

Currently in docs we have to access the core modules via relative paths e.g, import { useOnlineStatus } from '../../../src'; we need to replace it with import { useOnlineStatus } from @withvoid/melting-pot;

For this we need to add a plugin in the doczrc.js that handles an alias similar to what webpack does.

[adeelibr]

This helps with the discussion for this issue doczjs/docz#373 I have decided to opt for .babelrc option.

[adeelibr]

Resolved in #35