Twitter Connection Configuration details are not required to create connection

[mcada]

It is currently possible to create Twitter Connection with just name. It makes sense for me to mark its configuration fields as required or somehow tell the user that is was never validated thus it may not work - for example on icon of that connection - those icons are so big, maybe some small label with smart colour code and text: "Last validated: never/date of last validation" could come handy? What do you think?

[kahboom]

Related to #1193 (not the same though). Thanks @mcada !