Consul: Add heading name to the "no supports on more than X heading" alert

[bertocq]

Background

Currently, we limit the user supports to just one heading per Budget group. When the user tries to support in a second heading he gets the alert message You can only support investment projects in one heading

What we need

We need to include the heading name where the user has already supported. It will help clarify the error and even let the user undo the supports on that heading

Screenshot

One heading to support/vote

Example with various headings to support/vote

[aitbw]

I'm assuming this is already solved through #2528, right?

[decabeza]

Hi @aitbw, still not complete because we have the new "Maximum number of headings in which a user can support" attribute.

Now the message show the max heading you can vote but not the links to the other headings.

Actual message

We want this 😌

[mlovic]

I'll get started on this one