Add visual feedback when hovering over links and buttons

[hamteer]

Applicant Challenges:

• [x] blue border input fields
• [x] blue border select lists
• [x] hover response info button
• [x] blue border upload field

Admin Applications:

• [x] filter button: grey background
• [x] search button: darkgrey background

header:

• [x] hover response logout button

menu:

• [x] hover response menu options