Standardize radio/checkbox label styling

We currently have a mix of spacing, bold vs normal, description on the same line vs separate line, and description alignment with the actual input:

Screen_Shot_2017-11-03_at_7.47.02_AM

Screen_Shot_2017-11-03_at_7.47.30_AM

Screen_Shot_2017-11-03_at_7.48.31_AM

Screen_Shot_2017-11-03_at_7.48.50_AM

Assignee Loading
Time tracking Loading