Moving Draftjs plugin related code from Connect Repo

[RishiRajSahu]

After successful completion of this #2937 we can now work on moving the draftjs smart plugin code(to detect the links) to react-components library.

fyi @maxceem @vikasrohit

[maxceem]

Here is a sum up comment from a discussion regarding moving DraftJs editor to react-components:

@maxceem What are the other components for related to the DraftJS which we need to move? And I assume once we refactor them to react-components repo, it won't have any specific logic for Connect.

I think we only have to move DraftJs editor RichTextArea component as a component which would let us edit Rich Text. At the moment this component in Connect App is tightly bound with other Connect specific features. So the whole component renders next part:

It includes:

• field to edit title
• user avar
• Attach a file button
• Private switch
• Cancel and Post buttons

If we move this component to react-components we should only move Rich Text editor:

• the tricky thing would be to handle panel with buttons, as in our design it's mixed with other Connect specific functionality on the right. So on the one hand this panel should be quite independent from DraftJs component so we can put it where we want. On the other hand, it's tightly bound with DraftJs component, so if we keep this panel as a separate component, we should somehow bind functions of the buttons with DraftJs editor. Preferably, without writing a lot of code when reusing this component.

[vikasrohit]

Hold on for this for time being.