Changes to effect Issue2707

[airbr]

RE #2707 , Adding a paragraph telling if there is no upcoming conference, and also hiding add to event calendar button if there is no conference.

Thank you in advance for considering this pull request, it is my first attempted OSS contribution to a large project. Tried to keep it as small as I can and only touched the view.

Checklist

• [ YES ] I have read the Contribution & Best practices Guide.
• [ YES ] My branch is up-to-date with the upstream master branch.
• [ YES ] The tests pass locally with my changes.
• [ NO ] I have added tests that prove my fix is effective or that my feature works(if appropriate).
• [ NO ] I have added necessary documentation (if appropriate).

Short description of what this resolves/which issues does this fix?:

-Issue 2707

Changes proposed in this pull request:

Currently if there are no conferences the index view appears blank. This was pointed out that this could potentially confuse someone who maybe believes there has been a data error, and the conferences have been dropped. If current conferences is empty it seems easy to make these changes in the view file only to show the paragraph and hide the events button to resolve this issue.