Thai/sidebar fixes

[athai]

Resolves https://github.com/osu-cass/cass-pelican/issues/72, merge alongside https://github.com/osu-cass/cass-pelican/pull/74.

Bonus:

• Gap between slide show and navigation bar fixed
• Caption (for summary image) no longer "floats"
• Icons added to top hat

[Kennric]

Looks pretty good to me. +1

[kelnera]

@athai Is the "Make a Gift" button the donation button we were talking about?

[kelnera]

+1